Saturday, 6 February 2021

RETRO-MEASURE: Spendor SA1 (1976) monitor bookshelf speakers (The foam tweeter ring tweak!? And on "Listen For Yourself!".)

 

For this week's blog post, let's have a look at another "retro-measure"! This time, I had the opportunity to listen and test out the early-version Spendor SA1 speaker which hails from 1976. Remember that over the years, Spendor has released newer versions of this "classic"; most recently around 2009 as reviewed here in Stereophile.

This is another speaker I borrowed from my friend linnrd and I spoke about it back in late 2019 when I visited his place. This time, let's have a proper listen with measurements and compare the performance objectively and subjectively!

The "Spendor Mini Monitor Type SA1" came out just before the classic BBC LS3/5A design around 1975. Like the LS3/5A, these monitors were designed to be used in mobile recording vehicles.

As you can see in the image above, these are indeed >40-year-old speakers! There are cosmetic discolorations of the teak veneer but it's still looking quite good for something of this vintage, the box itself is constructed with birch internally I believe.

It's a 2-way closed speaker with 3/4" Son Audax tweeter and 6" Bextrene (polystyrene) mid-woofer. Crossover is at 3kHz.


As you can see, on the back, this is fitted with 5-way binding posts and can accept banana plugs. The Spendor stickers taped over the binding posts have long disappeared it looks like.

Dimensions are: 8.5" wide x 12" tall x 8.5" deep. Weighing just over 13lbs each.

Here's a closer look at the drivers on this old speaker. Notice the irregular texture on the surface of the doped Bextrene cone. Not the prettiest workmanship but this is the mid-'70s consumer tech!


Something else to note here is the presence of a foam ring around the tweeter! It reminds me of the squarish foam surrounding LS3/5A speaker tweeters to reduce cabinet edge diffraction. Interestingly, looking around the Internet, I could not find pictures of other old SA1's with this foam surround which looks quite old. I asked linnrd and got confirmation that indeed this foam ring was a later addition so for the main measurements, I'll take this off. I guess these were supposed to be some kind of "tweak" to improve sound.

The speaker grilles are cut out of a wood sheets covered in fabric. Plastic pin inserts secure them to the speakers:


I. Measurements

Alrighty then, here's a picture of the speaker ready for testing in the basement. Notice the foam ring around the tweeter removed; I actually measured with and without the ring to see what difference it made. As usual, the speaker was powered with my Emotiva XPA-1L amplifier. The DAC used for tone-generation is the Topping D10.

With foam ring around tweeter removed.

As passive speakers, it's good to start with impedance and sensitivity:


Impedance looks good and goes down to 7.6Ω at the lowest level, around 250Hz. Notice the EPDR (Equivalent Peak Dissipation Resistance) will dip down to 4.5Ω which is certainly not extremely low. There are 2 resonance peaks correlating with the 2 drivers at 66Hz and 1.3kHz. I don't see any discontinuities or irregularities in the impedance and phase curves at all! This suggests a well-dampened enclosure with minimal anomalous resonances.

Sensitivity calculated by average gated amplitude between 500Hz to 7kHz with a 2.83V sine sweep tone gives me a value of 85.4dB/2.83V/m. I believe these speakers were rated at 85dB/W/m so we're certainly in the ballpark. We can see from the +/-3dB red lines on the sensitivity calculation just how flat the frequency response appears.

Here's the CTA-2034A-inspired "qSpin" result:


As usual, my graphs are set to 25dB/decade aspect ratio with a Y-axis range of 30dB. The Spendor SA1 looks very good on the "qSpin"! The output level was measured at around 80dB SPL average on-axis and the "listening window" shows us that there is a bit of an accentuation up at 13.5kHz of about +2dB. There's a slight upper-mid and presence dip of about -2dB (4-5kHz). Bass has a -3dB point around 65Hz and -6dB of just above 50Hz. Certainly good for a relatively small, acoustic suspension speaker with a 6" woofer.

The Directivity Index looks like there's quite even dispersion into 10kHz and then the speaker narrows and "beams" into 20kHz which is not unusual. We can see this in the polar maps:


Below 10kHz horizontally, we see a nice and wide +/-60° dispersion pattern. On the vertical axis, it looks like it's best to listen between slightly above the speaker to around -15° for best sound. Furthermore on the vertical axis, you can see the effect of the crossover at 3kHz.

Along the time domain, here's the speaker step response:

Both tweeter and mid/woofer are arranged in positive acoustic polarity. The step response with its slight irregularity at 250µs suggests that the acoustic "center" is just below the tweeter axis and fits with the suggestion from the polar map that it might be best to listen to these speakers sitting with ear-level between the tweeter and mid/woofer.

The cumulative spectral decay "waterfall" graph looks good as well:


Again, this adds to the evidence that the enclosure is very well dampened with no concerns around resonance issues. You can compare this to the Radio Shack Minimus 7 which had a comparatively poor spectral decay.

Dynamics-wise, here's the multitone burst test for linearity between 70dB SPL to 100dB SPL, normalized to 0 at 85dB SPL:


At most around 1dB error across the 30dB range; not the best I've seen but I don't think the ears would mind at all.

Next up, let's look at distortions, here are some THD and IMD graphs:


The THD sweep graph looks quite typical of most speakers with portions of the spectrum showing more harmonic distortion. For this speaker, we see a little more THD between 2-3kHz. Otherwise, harmonic distortion remains well controlled below 1% (-40dB).


As for IMD, I must say that I am impressed by these 300/1300Hz IMD measurements from 60dB SPL to 90dB SPL! Consistently <1% distortion across the 4 output levels... Good stuff, especially given that these are >40 years old; I guess it's "broken in" but not "broken down"! :-)

Let's compare the stereo speaker pair I borrowed:






Overall, I like what I'm seeing here! Even after 40 years, we're still seeing maybe ~1dB difference in the frequency response between the two speakers. The impedance remains well matched. And the CSD likewise suggests that both enclosures are equivalently free from strong resonances.

A couple of final measurements. First, here's the difference between having the grille on versus taking it off:

It looks like the grille will dampen that 13.5kHz accentuation a little bit but otherwise, it functions quite transparently at least straight on tweeter axis.

And how about that add-on foam ring "tweak" stuck around the tweeter I showed above? Here's the "qSpin" graph with "tweeter ring" in place:

Compared to the "stock" SA1, notice that the foam ring introduced a suck-out into 9kHz on the order of -6dB and we also see a concomitant distortion in the Directivity Index. Here's what happened to the polar maps:


Notice the effect that a "tweak" like this had on speaker performance, easily demonstrable objectively even if one might not be able to hear it well (especially if one has limited high-frequency acuity). Needless to say, I would very much suggest that these foam rings be taken off the speaker unless one truly wants to suppress a significant portion of the frequencies in the "brilliance" audible spectrum. I suppose if  I listened to a lot of very poorly recorded/produced music with very harsh high frequency content, these might help. Even if I wanted to do this, a thinner ring would have been less heavy-handed, I suspect. :-)

Anyone know if it was popular to stick tweeter "diffraction rings" on back in the day?

II. Subjective


As in the picture above, I was listening to the Spendor SA1 with the foam rings in place as well as after taking them off prior to performing the measurements for about a week. The set-up is my usual, consisting of a combination of the Roon Server --> Raspberry Pi 4 streamer --> RME ADI-2 Pro FS R Black Edition DAC --> Emotiva XSP-1 preamp --> DIY Hypex nCore NC252MP amplifier. All hooked up with XLR balanced cables and DIY speaker cables.

You know how people say that "long-term listening" is the only way to know if something is good? In my experience this is untrue. Assuming one is playing a familiar song in a familiar room, I believe you can tell when you hear a great product within moments. This was what I felt about the Spendor SA1 even with the foam rings in place initially. The first song I listened to was Jennifer Warnes' "Bird On A Wire" (Famous Blue Raincoat) and by the end of the song, I knew I had to call my dad to come over and listen to these as he is particularly interested in vintage gear.

Simply beautiful, clean, balanced midrange right from the first notes and lyrics! These are really sweet speakers for vocals which I found rendered the human voice with a sense of reality and clarity that is highly desirable. The sense of "presence" was excellent on Roy Orbison's last album Mystery Girl with his unique vocals, and haunting sense of melancholy on songs like "In The Real World". I love how easy it was to emotionally connect to the music through these speakers and be transported back to a time when I first discovered Orbison's voice and became familiar with his work.

While sub-bass is too much of a reach, the bass on these speaker sound really good to me. Definitely not overaccentuated and certainly adequate to capture most of even large-scale performances. For example, I had a listen to Telarc's Erich Kunzel & Cincinnati Symphony Orchestra earlier version of the 1812 Overture with cannons and all. Excellent reproduction of the wide dynamic range, and even the cannons sounded reasonably credible even if not reaching fully deep enough in the audio spectrum. 

Taking the foam tweeter ring off liberated the perceived high-frequencies. A few weeks ago I watched and loved the new Pixar movie Soul with the family. Recently I bought a copy of the Soul soundtrack and love the juxtaposition of jazz compositions and piano work of Jon Batiste to represent the Earthly realm beside the ethereal score from Trent Reznor and Atticus Ross of the spiritual "beyond". The tracks "Falling", "Run/Astral Plane" and "Terry Time Too" benefitted nicely from taking the foam ring off by adding a bit more sparkle. I can see why some people might like to recess the "brilliance" portion of the audio spectrum and perceive this as creating a "warmer" sound that might be less fatiguing. That's fine so long as one understands the mechanism and recognizes the effect is not due to some magic. Without sticking any foam around the tweeter, this effect can be created by using a peak/dip parametric EQ of -6dB at 9kHz, Q value of 2.

One other new album I got recently was the 2CD set from the Eagles - Live From The Forum MMXVIII [2018]. While sadly this was recorded after the passing of Glenn Frey in 2016, Henley, Schmit, and Walsh were excellent and Deacon Frey and Vince Gill ("Don't Let Our Love Start Slippin' Away" is fun) performed alongside nicely. I appreciate that the recording maintained a good dynamic range of DR11 average although unfortunately, the production is of poorer quality than the excellent Hell Freezes Over from 1994. Definitely this is not worthy of "hi-res" (I don't think any live performances with an audience making noise are anyway). I've heard folks complain about the surround mix on the BluRay as well. The CD at least sounds decent and the presentation through these Spendor SA1's re-created a good sense of "surround" imaging of the band up front and illusion of being in the audience. This album can be a bit dull sounding so the foam tweeter ring is detrimental IMO.

I spent time with various other pop, classical and electronica albums as well which I'll reserve from spilling any more keystrokes on. All-in-all, a very satisfactory bookshelf-sized speaker!

III. Summary

I'm impressed! I don't think there's much more to say.

Spencer Hughes obviously knew what he was doing when he designed these back in the early 1970's and went into production by the mid-'70s. Given the vintage, I think it's natural to also think about the venerable BBC LS3/5A speakers of the day and the many fans of those speakers still (great site dedicated to LS3/5A). Remember that the LS3/5A is based on a smaller 5" mid/woofer; the SA1's 6" mid/woofer would/could/should achieve better bass extension. Maybe one of these days I'll have the opportunity to have one of those here at home for a listen and compare.

An inexpensive modern design similar to the Spendor SA1 might be something like the NHT SuperOne 2.1 speaker  (<US$180 each) - 2-way, closed box, similar dimensions, slightly larger 6.5" mid/woofer. I've heard good things about these, again maybe something I can check out in the future.

With the reasonable <100Hz extension that the SA1 provides, I think it would not be too hard to match these with a nice subwoofer in the living room crossed over around 80Hz and achieve some remarkable full-range playback. With a sensitivity of 85dB/W/m and good impedance profile, amplifier matching should not be difficult. If fact, it sounded great on my desktop with the SMSL SA300 Class D amp with only 30W into 8Ω although I would advocate for a good 100W amp for the living room to achieve that extra dynamic extension. If you haven't tried, it's worth estimating your amplifier power needs.

Of note, the results here look different from what was found in the Stereophile measurement of the new Spendor SA1 released in 2009. Lots of differences in terms of materials used for the drivers, enclosure design, crossover is different, and even the dimensions are different. Other than name and sealed-box design, I'm not sure what is even similar about these speakers.

Thanks again to linnrd for giving me the opportunity to listen and test these speakers!

--------------------

To end, I just wanted to spend a few minutes talking about that foam "diffraction ring" around the tweeter that was added by the original owner. Remember that over the years, people have used these in speaker designs, for example, here's a discussion of the application of this kind of "tweak" to the Acarian Alón Li'l Rascal Mk II speaker (see Addendum and also the Measurement changes) back in 2003.

Obviously the foam pad applied around the Spendor's tweeter resulted in profound effects which in my opinion were clearly undesirable.

If we were to talk to the previous owner who applied the tweak, he might have told us that the foam rings made a huge beneficial difference for him. While I would not be able to refute his subjective judgement or his experiential claims, to show you in the measurements what this tweak did to the sound I hope is a much more powerful disincentive to try doing such a thing knowing the effect regardless of what any one or more person(s) might testify! Again this is the power of taking an objective mindset and to seek facts rather than be satisfied with opinions.

An argument some audiophiles suggest is to "Listen for yourself!" to whatever tweak or supposed-beneficial products come our way. I obviously would not disagree either since personal experience counts for a lot on an individual level. But in practice, we obviously can't try everything the Industry produces or claims. Even if we were to buy a $1000 cable and likely return it due to lack of value, one would still have spent money at least on shipping costs assuming there were no international taxes or restocking fees. Better that we insist that companies come up with data and demonstrate the value of their products for us as consumers to consider first before anyone puts money down. Otherwise, the default position to take is that the product (and such companies) should be ignored if no evidence is forthcoming in my opinion.

Lastly for this week, reader Joe Pop sent me a link to this recent article by Brent Butterworth "The New Standard That Killed the Loudness War". It's reminiscent of this article by Ian Shepherd years ago in 2009 about loudness normalization with Spotify and the "end" of the Loudness War. Sadly, since 2009 there have been innumerable severely dynamically compressed new music for my liking. Well, let's hope it works out this time around. :-)

Take care and enjoy the music, audiophiles!

42 comments:

  1. Whoa, the measurements are certainly much better than I was expecting.

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    1. Why were you under that impression? First principles haven’t really changed.

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  2. Nice work. These are the kind of speakers folks like me who are older and need some HF boost would really benefit from this type of speaker. Clear, precise, and if you want more bass, just add a sub as you recommend which I think is ideal as then you can add just the right about of bass boost you want. Not ever LP or CD needs the same amount. I think these would be very nice monitors in a mastering suite.

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    1. I would caution against the pursuit of HF boost. If you listen to live acoustic music, and then listen to the reproduction over speakers with the boost, you are listening to something that doesn’t represent your reality. You are stating implying that you think the sound of a live saxophone is not real to you; there be dragons.

      I find it useful to consider tackling the problem at the fundamental level. Unless you use a hearing aid with built-in amplitude compensation at the frequency of your loss at all times or have a frequency compensating cochlear implant, you are already using a very good "equalizer" that resides between your ears. A good analogy for the problem in the visual domain is when one develops cataracts (which also involves a yellowing of your lens). When you see a white surface (a piece of paper) your retina gets transmitted an image that has a component of the blue filtered out. Over the years, you don’t see the paper as yellow because you “know” that it’s white. If you wear a pair of blue-tinted glasses, the paper will appear to be blue, although your retina is being transmitted a colour corrected image. You will only realize your colour imbalance once you get your cataracts removed. The ear-brain and eye-brain interfaces have an evolutionarily built-in error correction necessary for survival.

      I would submit that you consider tackling the problem at its heart, which is that YOUR reality has changed with your hearing loss and that is...OK. The path involving tipped up speakers is, literally, the path to self-delusion, imho.

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    2. But, my reality is flawed and at a concert at 73 I am not really hearing what someone with perfect hearing is. Someone with defective hearing may enjoy the concert, but we are not hearing it all.

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    3. Hey Jim,
      Notice that the increase in high frequencies >10kHz without the grille is actually very small, only about +2-3dB at most into 13kHz.

      Linnrd has a good point about the way our mind perceives sensory input. The brain is a powerful filter and over time adjusts whether it's white balance or our perceived frequency response.

      For personal listening, I'm curious if you or some of the older audiophiles purposely turn up the treble? Even if you're able to hear those frequencies (like >10kHz) better, does that sound more "euphonic" and preferable or because of daily experiences, make the sound less "natural"?

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    4. Hi all
      As an older audiophile, I don't tend to turn the treble up (doesn't help in the top octave) but I do find I prefer speakers which others might consider top-heavy or analytical (ESLs, LS50s.) Just more clarity, and more realism, especially with things like acoustic guitar or harpsichord.
      Also, when EQing or applying convolution, I tend to use a gentler treble rolloff than others.
      But I really think it depends to a great degree on what types of recordings you listen to. Close-miked studio recordings sound better with more rolloff. Blumlein or other 'natural' recordings (Water Lily, Alia Vox, Dorian) are usually okay with more hf energy (to my taste.) A good comparison of successful results of these 2 poles of recording technique would be Chesky's Rebecca Pidgeon tracks (e.g. Spanish Harlem) vs Alia Vox's Ninna Nanna with the late Montserrat Figueras (or any of the Baltimore Consort recordings on Dorian.) The close-miked Chesky tracks benefit more from convolution than the other style, to my ears. Same goes for most pop/rock recordings, especially with percussion.
      DSP now makes it easy to tailor the sound to our own preference or for the type of music/recordings we're playing. This is really valuable, as I don't believe that when it comes to speakers, one response curve fits all sources.
      Anyway, that's my two cents.
      Best wishes for 2021.

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    5. Thanks Phil,
      Very good point about the added complexity of the music production itself and the recording technique. Here again is another very important topic that affects sound quality to a major degree but I think "hardware" audiophiles don't pay enough attention to!

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    6. No I don't turn up the treble, but I can say that if someone finds a speaker bright, it probably won't seem that way to me. I find that I dislike added or bloated bass more than a lack of high frequency energy. I like bass control and extension.

      When I was able to attend concerts at Emory and Schwartz auditorium it was only to maintain my frame of reference as to what "real" sounds like. Of course with the pandemic that is not happening.

      I did discover from a Stereophile review of Reservoir Records a great pianist, Pete Malinverni and his recordings done my Jim Anderson are some of the most accurate sounding grand piano sounds I have ever heard. I now own 7 of his discs that are a steal at $10 + shipping from NY. If you want a Steinway reference, his sound is it.

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  3. Regarding the loudness wars, there is an interesting anecdote from (now retired) music producer Steve Lillywhite on Bob Lefsetz’s latest podcast about witnessing a mastering engineer adding an additional compressor/limiter to the mastering chain to “add a couple more decibels” *after* everyone had already signed off on the master. His point being that there are some artists that have been unwitting victims of crushed dynamics by unethical practices from people looking to make a name for themselves at the expense of the art.

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    1. Interesting comment Unknown,
      I would not be surprised that this happens although clearly that sucks!

      The question then is what might be motivating such a mastering engineer to do this? If somehow that motivation can be removed, then hopefully this would not happen.

      I suppose there are mastering engineers who are just deaf or following in the footsteps of people like Vlado Meller:
      https://www.soundonsound.com/people/vlado-meller

      Horrible.


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  4. Both Spendor and Rogers are highly acclaimed speakers, even to this day, if you don't expect miracles from them. They do what they do, but they do it very well.

    It would be interesting to see a similar article about the equally highly acclaimed Dynaco A-25 speakers, if that is possible. As far as I understand it, they were both cheaper and better than the tested Spendors and the Rogers LS3/5. Sadly, I think few sets have survived to this day.

    All taken into account, I would always prefer the reproduction from a 2-way speaker over 3-way or more. If needed, a good sub is the answer in a small listening room, where a tower may easily be too much. You can turn down the volume on a sub, but not the bass from a tower speaker. Imaging is also better from a standmounted speaker.

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    1. Hold my/Arch’s beer. ;-). I have a pair of A-35 that I personally much preferred to the A-25 I bought with them. They both have quite similar sonic signatures, but with the aperiodic slot venting into a sealed cavity the A-35 just seem that much more refined. Unfortunately, the A-25 went to a friend but measurements of the much rarer A-35 would be quite the coup.

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    2. A-25's come up regularly at Canuck Audio Mart as it was a popular speaker in its day. I've had several pairs as i have a fondness for non-ported speakers. I would be very interested in measurements of the A series and also some 70's AR speakers i've owned like the 16 or 18. Great works archimago!

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    3. Interesting stuff on the Dynaco, boys.

      Well linnrd, if you got that A-35 available, let's see what we can do in the days ahead :-).

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    4. Another Dynaco fan here. My first speakers were the A-25 along with an SCA-35 tube amp kit. Later after listening to a friend's large A-50, I updated to the A-40x, somewhat smaller but with the double compartiment cabinet. I have vague souvenirs of this one but fond memories of the A-25. I still own smaller A-10s that I used for a while as back speakers in a multi channel system. I would really be interested in a test round of the A-35.

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    5. As an old-time Dyna cultist, I've been keeping an eye out for a thrift-store pair of replacement cabinets for my A25 drivers, but today finally snagged a nice recapped pair of A25s locally.
      I will run a sweep or two and pass them on, but I'm not set up like Archimago or Amir, so don't expect much.
      Hooked them up to my Hypex amp and was immediately (nostalgically?) taken with the sound. I ended up putting the tweets to +1.
      Impressions are:
      - very nice, musical sound: male voices are very well handled
      - maybe a more 'coherent' sound than LS50s e.g.
      - some obvious lower mid-range, upper bass resonances (cabinet or vent needs retuning)
      - less clarity than more recent designs, obvious on Kavi's Meeting by the River: the tabla is recessed and the talking drum indistinct in pitch, and some obvious hangover. Some cabinet bracing/treatment might help.
      - HF rolloff irrelevant to my old tympanic membranes
      They will soon be joining their sister Dyna SCA80Q in my daughter's Mad Men retro system next to her martini bar (and I might feel a bit jealous.)
      So many people had these speakers back in the day, on the floor, behind couches, on bookshelves (they were sold as bookshelf speakers,) hooked up with frayed zip cord..., that we rarely heard them to their advantage.
      It's the journey.
      Best to all
      Phil

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  5. I have a pair of Spendor SP2/3e speakers. I know this is a totally different beast from another era, but Spendor seems to know what they’re doing. They’ve deserved their status as a reliably good brand.

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    1. Nice speakers Skyclad,
      Yeah, there's a lot of value to be had by spending more money on the speakers with good reputation for longevity!

      The fact that this pair has held out so well for so long certainly is very impressive!

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  6. Very fun review Arch!

    -- "You know how people say that "long-term listening" is the only way to know if something is good? In my experience this is untrue. Assuming one is playing a familiar song in a familiar room, I believe you can tell when you hear a great product within moments. " ---

    Yes, that's what I've been saying too for a long time. It takes me barely any time to get the gist of a speaker, especially with tracks I know.

    As for the Spendors, I admit it's sort of gratifying that you enjoyed the SA1 so much and that they measured pretty well. I'm nuts about my old Spendor S3/5s. I've kept them for decades even as various floor standing speakers have gone through my audiophile merry-go-round. Every time I throw the Spendors in to the system I'm just amazed at how good they are. Not the last word in anything, detail, impact, etc, but there is a sense of balance, of openness and "disappearing" yet without the instruments and voices becoming wispy or see-through. They have a sort of density and roundness. It's not for nothing the classic Spendors are renowned for vocals. I'll often close my eyes and simply listen to my wife's or my son's voice to get the gist of live voices, and then close my eyes listening to my hi-fi. Frankly, no other speaker has quite captured the gestalt of the human voice in this comparison like the Spendors. I just want to keep playing anything with vocals on them, as even vocalists mixed way back, or buried in production flourishes, seem to sound that much more human than on many other speakers.

    That's what I hear, anyway. Though I have to say the natural organic quality of voices sounds even more convincing powered by my CJ tube amps.
    I have a Bryston amp too at the moment and the Spendors don't have quite the magic with voices on the SS amp to my ears.

    Cheers, and keep 'em coming!

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    1. Are you familiar with Eva Cassidy's "Nightbird" album? I am absolutely in love with her music, and have this live album both on digital and analogue (180 g), and her voice and the instruments were recorded VERY well. I can recommend this album :)

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    2. “It's not for nothing the classic Spendors are renowned for vocals.”

      Absolutely! People forget that the remit for the engineers tasked with the LS project was to design a portable monitor (loudspeaker, hence the “LS” descriptor) for the BBC mobile mixing/monitoring units to minimize listening fatigue when working long shifts on a remote job, a lot of which involved spoken voice. The requirements were accuracy and consistency/interchangeability; in the event of the “disappearance” or malfunction of a single speaker, ANY single speaker from the storage could be substituted and form a matched pair in the mobile unit.

      It is a testament to the likes of Spencer Hughes and Dudley Harwood that the design continues to stand the test of time (over 45 years now). Unsurprisingly science workshop, which may be much to the chagrin of the “my subjective perception trumps your objective reality” camp.

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    3. Thanks for the comments guys...

      Yup, I have a tube amp sitting in my room currently and will definitely have a listen to Cassidy's Songbird (I think that's the album you're referring to, right Duck?) before I return them to linnrd. :-)

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    4. No, I am referring to Nightbird, which is the full concert, whereas Songbird is an album with a few of the songs from the full concert plus one studio track. Neither are bad albums, but there are several great songs on the Nightbird album which are not included on the Songbird album. On the latter there is only one track (the studio track, "Oh, had I a golden thread") which is not included on the full concert album.

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    5. Thanks Duck,
      Didn't even know Nightbird existed! I'll look for it...

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  7. I applied some felt strip around the inner edge of the grille on my SA1s, like the LS3/5a.
    That helped reduce the effect the grille had on the response
    I cant imagine anything worse than a thick circular ring around the tweeter!

    Derek

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    1. A square/rectangle instead of the ring? But, certainly nothing else springs to mind. :-)

      The ability of random people to believe they can improve a tested design by a team of qualified professionals merely by adding a piece of cheap foam displays a dangerously high level of hubris that I find rather disturbing to observe. That many other people get swept into their delusion is something that saddens me. (Green pens on CD edges, anyone?)

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    2. It can be necessary with some speakers.

      And about improving "a tested design by a team of qualified professionals", it indeed applies in multiple areas. I have personally improved both my turntable and several of my cartridges, both of which are indeed designed by qualified professionals. It only takes some insight, common sense, and the bravery to try it out. Nothing in this world is perfect.

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    3. Well, that thick round foam was certainly a bit heavy handed :-).

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    4. - which is why most audiophiles with such a need soon switched to gluing a piece of black felt to the front place around the tweeter, and adding some foam, cloth or felt to the inside edges of the grille.

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  8. I still have a pair of Rogers LS3/5as that were designed for the same situation. Mine are the much improved 11 Ohm version, and that probably explains why they still sound pretty good. The older 15 Ohm version was very hard to produce to specification(hence the redesign)and also prone to deterioration, as Harbeth's Alan Shaw has shown with distressing measurement examples. I used mine as desktop monitors, but replaced them some years ago with their modern reincanation, the Harbeth P3ESR. Those are quite clearly a lot better - technology has moved on, even though the LS3/5a was a lovely speaker.

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    1. Thanks for the note Willem.

      One of these days, I'll get my hands on the LS3/5a and have a listen/look. Certainly the interest in those speakers and "following" is impressive! Speaking of the P3ESR, I did have a listen to them a few years ago but not in a familiar room; sounded pretty good and I thought the bass extension was better than anticipated!

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  9. In the late 70'es I had another version of the Dynaco A25's, a Danish "clone" called Scan Dyna E30. Same design as the A25 with the acoustic valve and all, and they sounded sweet too. Kind of sad I let them go, but I am more than happy with my current Dynaudio Contour 20'es.

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  10. This is my first comment in one of your posts, so first i must thank you for your effort, and assure you of the value I attach to the whole of your postings.

    What has caught my attention of this review of the SA1 is that you considered that the bass was good enough.
    Logically, the average hi-fi reviewer has a better listening room than those of us that live in smallish appartments, usual in european cities. So there are many articles around about the ideal frequency response curves, down to deep bass, but not about acceptable ones, like night modes, very useful when neighbours are a pressing concern. I will thus use the frequency response of the SA1 as a reference to equalise my loudspeakers, and will welcome any ideas or links in this regard.

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    1. Yeah, a frequency response that is flat as a ruler is not desirable in living rooms, or most other places. We all have different rooms, furniture, damping, gear and taste. Synergy and balance comes into play as well. The funny thing is IMO, that we strive to get the sound of the "original event", even though we can never reach that goal, but what else do we have as a reference?

      If we are skilled and lucky we may reach a point in our reproduction, where we can be happy, and our brains recognize the sound quality as "close enough", and release a bunch of endorphins into our bodies when we listen to the music we love. This is our goal, whether we realize it or not.

      So my point is, that there's no ideal frequency response as such, only the ideal one for each of us, which can take forever to accomplish.

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    2. Edit:
      I have been listening to music all my life, right from when I wore diapers, and I've been into hifi since 1968. I didn't reach the above mentioned point of fidelity until I retired in 2017...

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    3. Hi Anibal,
      Welcome and thank you for the very practical comment. Likewise Duck's comment about the importance of individual experience.

      I learned about this a number of years ago when I lived in an apartment. I had a number of complaints after buying my floor stander Paradigm Studio 80 speakers whereas nobody complained previously with some small standmount Tannoy mX2. :-)

      Remember that the frequency response measurements are derived as a quasianechoic reading at 1m. Empirical research suggests that we want a smooth and flat "listening window" curve (black) and at our listening position, a tapered dip into 20kHz like that "Early Reflections" curve (blue).

      I think a bass response like this is a good compromise. Relatively flat down to 80Hz, and then rolling off with -6dB by about 50Hz should not give adjacent tenants too much of a headache - all dependent on your building's sound isolation of course! You'll still be able to appreciate the bass in your music.

      PSB has a nice chart labeled "The Frequencies of Music":
      https://www.psbspeakers.com/the-frequencies-of-music/

      Notice that there are not that many acoustic instruments that go down below 50Hz so that's a reasonable frequency landmark to think about for "natural" sounding music.

      The compromise of course means there won't be much sub-bass especially for electronic and pop music. For those frequencies, maybe a small sub turned on only during the daytime with reasonable neighbours in the building would be the only option.

      Try as we might, generally it is impossible to achieve ruler-flat frequency response as per Duck's comment. Which then of course brings up the who topic of room acoustics, optimization, EQ, and personal preference to a certain degree of course...

      All the best and enjoy your music!

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    4. Thanks Arch, very true indeed!

      I have floorstanders with a -3 dB point of 39 Hz, and as such I don't feel I need more bass. Still, my son mainly listens to death metal (yuck!), which is of no interest whatsoever to me, lol. He lives far away and only visits once in a while.

      I am 68, and my taste in music is based on memories for the most part, although I do listen to the newest releases as well, but my taste has grown softer throughout the years. Led Zeppelin and such music is still in my collection, although I don't spin it as often any longer.

      My son told me that I desperately need a subwoofer, and just to make him happy, I will have a listening session on Tuesday at home. I have chosen a relatively modest one, a Rel T7i, which don't go very deep, and has a modest size compared to the "earthquake models" some movie enthusiasts like. It's a 200 Watts powered unit with a -6dB point at 30 Hz. This is just an addition of about half the bottom octave, but I feel it will suit both my own needs and those of my son. Side speakers are Dynaudio Contour 20'es. The thing I worry most about is integration, but since these Rel subs are said to be easy to integrate, I am looking forward to the audition in my living room on Tuesday. They bring it to me, set it up, and give me some time to listen. In case I can't make it work, they fetch it again. Thank God for hifi shops with excellent service :)

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    5. The sub arrived for a listening session today. It's a Rel T9i, the only model my hifi-shop has available at the moment. But the difference between the two models is rather small; the T9i has 300 Watts and a front firing unit of 10", while the T7i has 200 Watts and a front firing unit of 8". The slave in both models is a 10" down firing unit, and both models display a -6dB point at 30 Hz.
      Since my room is rather small, and because I clearly felt the rather "overwhelming" power of the T9i, I decided on the spot that the smaller model would be more than sufficient.
      The sub works superbly with both my Dynaudio Contour 20'es and my room, not being too much with the settings I settled for. I chose a very low crossover frequency and volume. I firmly believe one shouldn't hear the sub as such, but hear something's missing when it's turned off. Some may disagree, I know, but I've purchased it for stereo, not home theater.

      I'll have the sub on loan for some days to come, but as this brand is made in Wales, there's unfortunately a rather long time until I can settle in with my very own T7i. It will arrive in April. *SIGH*

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    6. The only "setback" is that there's generally more deep notes on CD's and flac files than on LP's, so the audible volume of the sub is lower with LP's.
      I can live with it, though...

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  11. Hi, I need to replace the Audax tweeter of my Spendor SA1 Mini Monitor, any suggestion where I can find it?

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  12. ps. it's the early version of the '76

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