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Gryphon Mono Preamplifier by 2R (vintage) Review

Pinox67

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Below is a review of this high-end '90s preamp from a (lucky) friend.

BUILD
The Mono Preamplifier has an excellent build quality, perfectly in line with the philosophy of this prestigious Danish brand. It is worth mentioning that all Gryphon products are designed and manufactured in Denmark. Electronic components meet military or medical grade specifications. The assembly is entrusted to subcontractors who offer the most advanced techniques. And each unit is tested individually; After a 48-hour burn-in, each product is again subjected to both electronically and audio performance tests.

Returning to the Mono Preamplifier, this one has a completely dual mono configuration: electronics, containers and controls are separate for each channel. The only part they share is the black perspex front plate and a pair of golden spacers between the containers. The look is minimalist and elegant, with the controls consisting solely of the input selector and volume control, crafted from large gold discs with rosewood centers. At the base four black ceramic tips.

1648321556225.jpeg

On the back there are the golden WBT connectors for inputs and outputs, and the screw connectors for the power supplies (not shown in the photo) separated for each channel and duplicated for the line and phono part (optional).
The power supplies are equipped with noise filters. Gryphon recommends leaving the preamp on all the time, given the long warm-up times.

1648321612596.jpeg


I was unable to retrieve much technical information. The volume control is made with 24 passive resistors, assembled by hand. The electronics are completely discrete, the shortest possible signal path with internal wiring. The preamps work in pure Class X 100 with C-core transformers equipped with noise filters. The phono MC offers the possibility of being able to change the impedance by inserting resistors on the Load input.

In the ’90s, the price was almost $5000: today on the second-hand market it has prices around $4000.


MEASUREMENTS
All following measurements have been made with RME ADI2 Pro FS, only for the line stage, where:

- Input/Output: RCA; from DAC/ADC with resolution 24/192
- Load: 9 KOhm

For the electrical aspects we have:

- Gain: 21dB max
- Output impedance: 51Ohm (measured in all audio band)


FREQUENCY RESPONSE

Input: 2.5Vrms Tone sweep; Gain: 0dB – LR Module
1648318504870.jpeg

The Mono Preamp preamp has an ultra-wide, flat bandwidth well beyond the audible band, with the two channels perfectly balanced, after 30 years of work… Wow!

Input: 2.5Vrms Tone sweep; Gain: 0dB – LR Phase
1648318744587.jpeg

Also in the phase shift we see the same excellence: distortion is 0 also at 10Hz, despite the low load, 9KOhm. This means a coherence for bass. An analogous situation is the high frequencies 20KHz, with a shift near to 0. Another Wow!

Input: 2.5Vrms Tone sweep; Gain: 0dB – R Channel and Loopback Step Response
1648318853782.jpeg

The excellence of the module/phase frequency response can be seen also in the step response, where the measurement device loopback curve and the preamp curve are perfectly overlapped.


CROSSTALK

Input: 2.5Vrms Tone sweep; Gain: 0dB – LR/RL Crosstalk
1648318936125.jpeg

Thanks to the complete dual mono construction, there is no doubt about channel separation, beyond 110dB, the accuracy of the measuring device.


SINGLE TONE DISTORTION

Input: 2.5Vrms @ 1KHz; Gain: 0dB – R Spectrum
1648319168399.jpeg

At 2.5Vrms input, 0dB Gain we have: THD = -77.5dB; THD+N = -77.0 dB (not weighted)
The distortion is practically due to second (-78dB) and third harmonic (-85dB); higher harmonics are not measurable, because they are at the same level of the measurement device, below -130dB. Excellent also the level of noise due to 50Hz power supply, practically absent, below -130dB.

Input: 0.625Vrms @ 1KHz (-12dB); Gain: 0dB – R Spectrum
1648319311871.jpeg

With a smaller signal of -12dB the second and third harmonics go down, more in the third and less in the second one, as expected.


HARMONIC DISTORTION PER FREQUENCY/LEVEL

Input: 2.5Vrms Sine @ 10Hz-90KHz; Gain: 0dB – HD per Frequency
1648319513158.jpeg

At 2.5Vrms the THD is 0.012%, practically constant for all frequencies and due mainly to the second harmonic. The third one is around 0.005%. All others higher harmonics overlaps with that of measurement device (so, no measurable).

Input: 1.0Vrms Sine @ 10Hz-90KHz; Gain: 0dB – HD per Frequency
1648319649342.jpeg

At 1.0Vrms the THD goes to 0.005%, still practically constant for all frequencies, due to the second harmonic. The third one is around 0.0007%. Negligible the difference for the other channel (not shown).

Input: 2.5 – 0.15Vrms Sine @ 10Hz-90KHz; Gain: 0dB – THD per Frequency and Level (3dB steps)
1648319774910.jpeg

The THD shape, decreasing input level from 2.5 to 0.15Vrms in step of 3dB, shows a substantial independence from signal level (deviations on high frequencies of lower ones are affected by resolution and noise).

Input: Step level 0dB = 2.5Vrms; Tone @ 997Hz; Gain: 0dB – HD per Level
1648319969113.jpeg

The distortion is dominated always by the second harmonic, already present at low levels (-26dB). The third one starts to raise from noise at -16dB; other ones are practically absent. This means limited dependance of signal characteristics from the listening level.


INTERMODULATION

Input: 2.5Vrms Dual Sine @ 19 + 20KHz; Gain 0dB – Spectrum R
1648320132540.jpeg

Good also the CCIF test: IMD is -76dB. Symmetrical non-linearities (here only of third order), near input signals, are about -83dB; asymmetrical, even-order distortion (here only of second order) at 1KHz is -76dB; TD+N is -73.5dB. No difference (not shown) between channels.

Input: Multi Sine @ 1/3 Octave; Gain 0dB – Spectrum R
1648320231684.jpeg

The distortion floor is below -90dB, that means about 15bit of signal without artefacts.


LISTENING TEST
The measurements above suggest that the Gryphon Mono Preamplifier is fast, silent, and should behave transparently, given the characteristics of the non-linear distortions: constant in frequency, and similar for the different signal levels; moreover, even if not very small, they are still "benign" for our ear if not for improvement. These aspects, combined with the extension and precision of the frequency response, in module and phase, and the non-existent crosstalk, should contribute to the construction of a good soundstage.

And in fact, in the listening test, it is like this: it is silent and non-intrusive; detailed but not tiring; it combines the analytical properties of reference devices with musicality. Its sound staging capabilities is also remarkable: it offers a wide and deep soundstage, with clearly distinguishable images of sound objects. To better qualify these qualities, a direct comparison with two other high level preamps that I was able to test in the same days can help: the Threshold FET10/e and the Mark Levinson N.26, both known for being considered very transparent. All preamps are inserted in my reference chain consisting of: Esoteric D05X DAC; Krell KMA160 power amp; Wilson Sasha II loudspeaker. The room is acoustically treated.
Well, compared to the FET10/e, with controlled listening level (however not blinded, for obvious reasons), the Mono Preamplifier resulted with more body, with a better soundstage and with a slightly (and pleasantly) "smooth" sound. Even compared to the N.26 it was a little less transparent, but the N.26 manages to return a wider and more precise soundstage. On other aspects, I did not notice any relevant differences.

In conclusion, the Gryphon Mono Preamplifier is still a current, highly desirable device with out-of-class performance, probably one of the best preamps I have ever tested in my system.
 
Last edited:

Gorgonzola

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Price?

Looks like the Gryphon is very low in in distortion overall. Distortion that the is is almost entirely 2nd followed by slightly lower 3rd order; higher orders are very low.

The levels of 2nd and 3rd that are present will never be hear as distortion per se, but will add a light caramel drizzle to the listening cake.
 

fredoamigo

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I always wondered how one could listen to what is transparent.
listening to transparency seems to me to be one of the most difficult tasks in audio. Unless there is more transparent than transparent?
 

anmpr1

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As good as it is, it is not really a true twin, or true dual mono preamp. You can tell because of the faceplate. The 'uniplate' connecting the two individual preamp chassis makes this design one in a category known as a 'pseudomonophonic' device, with all the sonic problems inherent to this sort of topology. Essentially the folks at Gryphon have sacrificed sonic clarity for convenience and cost-cutting. The big problem they have neglected to address is the 'front plate skin effect' that occurs whenever you attach two separate components in series.

This problem has an interesting history, and was accidentally discovered by Stereopile editor J. Gordon Dolt, in the early days of stereo, when he noticed that two individual (and true mono) Dynakit PAM preamplifiers sounded better, with more detail, front to back depth, and air between the clicks and pops of his records, than they did when connected together using the optional Dyna DSC-1 stereo control center module.

pam.jpg


The designer, David Baffler, was frankly baffled, and in a letter to the editor told Gordy that his 'subjective' impression was likely due to the particular full moon phase present during the time of his audition, plus the moon's gravitational effect on Dolt's precious bodily fluids circulating throughout his brain. Baffler suggested that he try listening during a waning gibbous, and then compare that with the sound during a waxing crescent, making sure to wear a blindfold during the test so as not to be influenced by external factors, such as stray moonbeams.

However, the problem was independently investigated by the scientists at the Six Moons over Miami operation, and they concluded that Dolt was essentially correct-- that it wasn't the moon at all, but something else was going on. After all, Dolt was just working with one moon, but they had six to make a comparison with, and sure enough the sonic differences were there. They did take a more nuanced stance from the former's description of the effect, instead reporting that the air on the record's pops and clicks were not really reduced, but rather it was the subjective soundstage that had changed, from one similar to the Royal Concertgebouw (with two mono PAMs), to one more like Lincoln Center, in NYC (with the DSC-1). It was most evident on Elvis Presley 45 rpm records from Sun, although other records from Sun, those from Sun Ra released on El Saturn, were used during the audition.

Much ink was spilled over the issue, back and forth. Gillian Gersh, at Audio Review, counted the knobs on the two preamps, and concluded that the two PAMs with the DSC-1 was better, because it had more knobs and switches, for the money. Using his Bose 901s as a reference, Gillian stated that he couldn't hear any difference between the two. High Infidelity technical editor, Larry Blind, agreed.

The most promising theory arguing for the effect was probably that coming out of Helsinki, from Hattie Lotala, and her stateside colleague, Enid Dumley, who suggested that the problem was one they called Transient Interconnectivity Distortion, which happened when two circuits were passively bolted to (but not electrically connected to) a single metal chassis. But they concluded it was impossible to detect under 'steady-state' conditions, and in fact they didn't have any definitive way to 'measure' the effect, one way or the other.

For her part, Dumley suggested that it could have something to do with 'stray' magnetic fields, and after consulting with magnetic field authority Bob Larder, theorized that wrapping common household electrical motors with Reynolds wrap, might help. She then proceeded to wrap her refrigerator in aluminum foil, and reported that although this improved the music's low-level plankton, once it was all enclosed in tin foil it was impossible to open her refrigerator door to get out beers. However it was not a total loss, because she had enough left on the roll to make herself a nice little hat, which she was quite proud of, and got her a lot of admiring looks whenever she went out of doors, shopping.

The issue was finally solved when Clark Levinsun teamed up with John Hurl, to create the CJ-6abc preamplifier, consisting of not only two separate unconnected chassis, but two separate power supplies. The fact that it cost more money than God had in his checkbook was of little moment to true audiophiles, for whom money is always secondary to audio nirvana.

However, science never stops, and research is still on-going. Recently, Audiobest company found that replacing the CJ-6abc power cable with two of their Constant Current Sharknado Typhoon power cords resulted in an even greater sonic improvement. Saul McGowen made further progress by building a dedicated power conditioner (designed by Baskin Queen, with FET output, and tube input stage) for the CJ-6abc, but since these are mono preamps, you need two of them for best results.

Finally, scuttlebutt from the field has it that some guy named Amir, at an operation called ASR, is going to do some independent investigation, and maybe post a Yoo Hoo video, in order to finally get to the bottom of the problem. If it is a problem at all. Expect good news soon.

PS: apologies to the folks at Gryphon, who appear to have made a pretty nice preamp (if black and gold are your thing).
 
OP
Pinox67

Pinox67

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I always wondered how one could listen to what is transparent.
listening to transparency seems to me to be one of the most difficult tasks in audio. Unless there is more transparent than transparent?

Every device in our reproduction chain inexorably modifies the signal passing through it. In the audio field (but not only) transparency is associated with the fact that changes on sound are for our ear of very limited magnitude. Of course, the question is: how to understand it?

We need a reference. One way forward is as follows: Compare the sound resulting from a good playback chain with the preamp inserted and without. Of course you need to have a source (CD player or DAC) that has volume control to be able to connect it directly to the power amplifier. If, on blind evidence, the differences are undetectable or negligible, then you can say that it is transparent. If, on the other hand, the characterisations are clearly noticeable, it is not (and that’s not necessarily a flaw).

The next problem is to quantify these deviations (coloration, spatiality, detail etc.), which certainly cannot be represented by numbers or graphs. Here it can help to refer to other preamps that are more widespread and known as characteristics, as I added in the test. Yes, everything is very empirical and the variables are many. And that’s also the beauty of this hobby.
 
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fredoamigo

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I assume that a preamplifier should not have a sound and if it has a sound is that a wolf is hiding in the sheepfold.
Since this one seems to be correctly built, it would have been in my opinion useful to make a small blind AB comparison with the RME ADI since it seems that you have one at home and I would be really curious to know the result?

For the spatialization and as far as I know, this one emanates essentially from the directivity/radiation of the speakers and the interaction of these speakers with the walls as well as the sound recording/mixing/mastering...you should explain to me what the preamplifier has to do with it ? moreover "transparent" what role does it have ?

Don't see any malice in my questions, if there are answers that hold the road I'm a taker!
In any case, congratulations for your measurements and your review (I am not an objectivist machine but a poor human trying to learn and understand)
 
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Pinox67

Pinox67

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I assume that a preamplifier should not have a sound and if it has a sound is that a wolf is hiding in the sheepfold.

You assume well. But this is true in theory, the reality is different. Try changing preamps in your chain (perhaps borrowed from some friends) and listen to the result. Some may be indistinguishable; with others there will be more substantial differences. The reason is that any device introduces own distortions, more or less audible and in some cases wanted expressly by the designer to produce a sound less faithful but more pleasant. A simplified description of the types of distortion and their effects can be found in this post, while an in-depth look at nonlinear distortions effects is in this thread.

Since this one seems to be correctly built, it would have been in my opinion useful to make a small blind AB comparison with the RME ADI since it seems that you have one at home and I would be really curious to know the result?

I ran the AB test with the Threshold FET10/e, as described here. I use this preamp as reference.

For the spatialization and as far as I know, this one emanates essentially from the directivity/radiation of the speakers and the interaction of these speakers with the walls as well as the sound recording/mixing/mastering...

You are right. I also add the isolation aspects of loudspeakers (and of electronics) plays an important role.

you should explain to me what the preamplifier has to do with it ? moreover "transparent" what role does it have ?

The main parameters here are crosstalk and frequency response, especially the medium-high frequency phase distortion. I’m conducting in-depth tests on the effects of these aspects, I’m going to start a thread on this subject.

Don't see any malice in my questions, if there are answers that hold the road I'm a taker!

No problem, we are all here to confront and learn.
 
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Vini darko

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As good as it is, it is not really a true twin, or true dual mono preamp. You can tell because of the faceplate. The 'uniplate' connecting the two individual preamp chassis makes this design one in a category known as a 'pseudomonophonic' device, with all the sonic problems inherent to this sort of topology. Essentially the folks at Gryphon have sacrificed sonic clarity for convenience and cost-cutting. The big problem they have neglected to address is the 'front plate skin effect' that occurs whenever you attach two separate components in series.

This problem has an interesting history, and was accidentally discovered by Stereopile editor J. Gordon Dolt, in the early days of stereo, when he noticed that two individual (and true mono) Dynakit PAM preamplifiers sounded better, with more detail, front to back depth, and air between the clicks and pops of his records, than they did when connected together using the optional Dyna DSC-1 stereo control center module.

View attachment 196137

The designer, David Baffler, was frankly baffled, and in a letter to the editor told Gordy that his 'subjective' impression was likely due to the particular full moon phase present during the time of his audition, plus the moon's gravitational effect on Dolt's precious bodily fluids circulating throughout his brain. Baffler suggested that he try listening during a waning gibbous, and then compare that with the sound during a waxing crescent, making sure to wear a blindfold during the test so as not to be influenced by external factors, such as stray moonbeams.

However, the problem was independently investigated by the scientists at the Six Moons over Miami operation, and they concluded that Dolt was essentially correct-- that it wasn't the moon at all, but something else was going on. After all, Dolt was just working with one moon, but they had six to make a comparison with, and sure enough the sonic differences were there. They did take a more nuanced stance from the former's description of the effect, instead reporting that the air on the record's pops and clicks were not really reduced, but rather it was the subjective soundstage that had changed, from one similar to the Royal Concertgebouw (with two mono PAMs), to one more like Lincoln Center, in NYC (with the DSC-1). It was most evident on Elvis Presley 45 rpm records from Sun, although other records from Sun, those from Sun Ra released on El Saturn, were used during the audition.

Much ink was spilled over the issue, back and forth. Gillian Gersh, at Audio Review, counted the knobs on the two preamps, and concluded that the two PAMs with the DSC-1 was better, because it had more knobs and switches, for the money. Using his Bose 901s as a reference, Gillian stated that he couldn't hear any difference between the two. High Infidelity technical editor, Larry Blind, agreed.

The most promising theory arguing for the effect was probably that coming out of Helsinki, from Hattie Lotala, and her stateside colleague, Enid Dumley, who suggested that the problem was one they called Transient Interconnectivity Distortion, which happened when two circuits were passively bolted to (but not electrically connected to) a single metal chassis. But they concluded it was impossible to detect under 'steady-state' conditions, and in fact they didn't have any definitive way to 'measure' the effect, one way or the other.

For her part, Dumley suggested that it could have something to do with 'stray' magnetic fields, and after consulting with magnetic field authority Bob Larder, theorized that wrapping common household electrical motors with Reynolds wrap, might help. She then proceeded to wrap her refrigerator in aluminum foil, and reported that although this improved the music's low-level plankton, once it was all enclosed in tin foil it was impossible to open her refrigerator door to get out beers. However it was not a total loss, because she had enough left on the roll to make herself a nice little hat, which she was quite proud of, and got her a lot of admiring looks whenever she went out of doors, shopping.

The issue was finally solved when Clark Levinsun teamed up with John Hurl, to create the CJ-6abc preamplifier, consisting of not only two separate unconnected chassis, but two separate power supplies. The fact that it cost more money than God had in his checkbook was of little moment to true audiophiles, for whom money is always secondary to audio nirvana.

However, science never stops, and research is still on-going. Recently, Audiobest company found that replacing the CJ-6abc power cable with two of their Constant Current Sharknado Typhoon power cords resulted in an even greater sonic improvement. Saul McGowen made further progress by building a dedicated power conditioner (designed by Baskin Queen, with FET output, and tube input stage) for the CJ-6abc, but since these are mono preamps, you need two of them for best results.

Finally, scuttlebutt from the field has it that some guy named Amir, at an operation called ASR, is going to do some independent investigation, and maybe post a Yoo Hoo video, in order to finally get to the bottom of the problem. If it is a problem at all. Expect good news soon.

PS: apologies to the folks at Gryphon, who appear to have made a pretty nice preamp (if black and gold are your thing).
Hahahaha good story
 

changster

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My last preamp was a Gryphon Mirage (paired with Gryphon Antileon Signature monoblocks). It'd be really interesting to see them tested. I still have them sitting around, lol.
 

Chrise36

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As good as it is, it is not really a true twin, or true dual mono preamp. You can tell because of the faceplate. The 'uniplate' connecting the two individual preamp chassis makes this design one in a category known as a 'pseudomonophonic' device, with all the sonic problems inherent to this sort of topology. Essentially the folks at Gryphon have sacrificed sonic clarity for convenience and cost-cutting. The big problem they have neglected to address is the 'front plate skin effect' that occurs whenever you attach two separate components in series.

This problem has an interesting history, and was accidentally discovered by Stereopile editor J. Gordon Dolt, in the early days of stereo, when he noticed that two individual (and true mono) Dynakit PAM preamplifiers sounded better, with more detail, front to back depth, and air between the clicks and pops of his records, than they did when connected together using the optional Dyna DSC-1 stereo control center module.

View attachment 196137

The designer, David Baffler, was frankly baffled, and in a letter to the editor told Gordy that his 'subjective' impression was likely due to the particular full moon phase present during the time of his audition, plus the moon's gravitational effect on Dolt's precious bodily fluids circulating throughout his brain. Baffler suggested that he try listening during a waning gibbous, and then compare that with the sound during a waxing crescent, making sure to wear a blindfold during the test so as not to be influenced by external factors, such as stray moonbeams.

However, the problem was independently investigated by the scientists at the Six Moons over Miami operation, and they concluded that Dolt was essentially correct-- that it wasn't the moon at all, but something else was going on. After all, Dolt was just working with one moon, but they had six to make a comparison with, and sure enough the sonic differences were there. They did take a more nuanced stance from the former's description of the effect, instead reporting that the air on the record's pops and clicks were not really reduced, but rather it was the subjective soundstage that had changed, from one similar to the Royal Concertgebouw (with two mono PAMs), to one more like Lincoln Center, in NYC (with the DSC-1). It was most evident on Elvis Presley 45 rpm records from Sun, although other records from Sun, those from Sun Ra released on El Saturn, were used during the audition.

Much ink was spilled over the issue, back and forth. Gillian Gersh, at Audio Review, counted the knobs on the two preamps, and concluded that the two PAMs with the DSC-1 was better, because it had more knobs and switches, for the money. Using his Bose 901s as a reference, Gillian stated that he couldn't hear any difference between the two. High Infidelity technical editor, Larry Blind, agreed.

The most promising theory arguing for the effect was probably that coming out of Helsinki, from Hattie Lotala, and her stateside colleague, Enid Dumley, who suggested that the problem was one they called Transient Interconnectivity Distortion, which happened when two circuits were passively bolted to (but not electrically connected to) a single metal chassis. But they concluded it was impossible to detect under 'steady-state' conditions, and in fact they didn't have any definitive way to 'measure' the effect, one way or the other.

For her part, Dumley suggested that it could have something to do with 'stray' magnetic fields, and after consulting with magnetic field authority Bob Larder, theorized that wrapping common household electrical motors with Reynolds wrap, might help. She then proceeded to wrap her refrigerator in aluminum foil, and reported that although this improved the music's low-level plankton, once it was all enclosed in tin foil it was impossible to open her refrigerator door to get out beers. However it was not a total loss, because she had enough left on the roll to make herself a nice little hat, which she was quite proud of, and got her a lot of admiring looks whenever she went out of doors, shopping.

The issue was finally solved when Clark Levinsun teamed up with John Hurl, to create the CJ-6abc preamplifier, consisting of not only two separate unconnected chassis, but two separate power supplies. The fact that it cost more money than God had in his checkbook was of little moment to true audiophiles, for whom money is always secondary to audio nirvana.

However, science never stops, and research is still on-going. Recently, Audiobest company found that replacing the CJ-6abc power cable with two of their Constant Current Sharknado Typhoon power cords resulted in an even greater sonic improvement. Saul McGowen made further progress by building a dedicated power conditioner (designed by Baskin Queen, with FET output, and tube input stage) for the CJ-6abc, but since these are mono preamps, you need two of them for best results.

Finally, scuttlebutt from the field has it that some guy named Amir, at an operation called ASR, is going to do some independent investigation, and maybe post a Yoo Hoo video, in order to finally get to the bottom of the problem. If it is a problem at all. Expect good news soon.

PS: apologies to the folks at Gryphon, who appear to have made a pretty nice preamp (if black and gold are your thing).
You got talent really
 

DavidEdwinAston

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As good as it is, it is not really a true twin, or true dual mono preamp. You can tell because of the faceplate. The 'uniplate' connecting the two individual preamp chassis makes this design one in a category known as a 'pseudomonophonic' device, with all the sonic problems inherent to this sort of topology. Essentially the folks at Gryphon have sacrificed sonic clarity for convenience and cost-cutting. The big problem they have neglected to address is the 'front plate skin effect' that occurs whenever you attach two separate components in series.

This problem has an interesting history, and was accidentally discovered by Stereopile editor J. Gordon Dolt, in the early days of stereo, when he noticed that two individual (and true mono) Dynakit PAM preamplifiers sounded better, with more detail, front to back depth, and air between the clicks and pops of his records, than they did when connected together using the optional Dyna DSC-1 stereo control center module.

View attachment 196137

The designer, David Baffler, was frankly baffled, and in a letter to the editor told Gordy that his 'subjective' impression was likely due to the particular full moon phase present during the time of his audition, plus the moon's gravitational effect on Dolt's precious bodily fluids circulating throughout his brain. Baffler suggested that he try listening during a waning gibbous, and then compare that with the sound during a waxing crescent, making sure to wear a blindfold during the test so as not to be influenced by external factors, such as stray moonbeams.

However, the problem was independently investigated by the scientists at the Six Moons over Miami operation, and they concluded that Dolt was essentially correct-- that it wasn't the moon at all, but something else was going on. After all, Dolt was just working with one moon, but they had six to make a comparison with, and sure enough the sonic differences were there. They did take a more nuanced stance from the former's description of the effect, instead reporting that the air on the record's pops and clicks were not really reduced, but rather it was the subjective soundstage that had changed, from one similar to the Royal Concertgebouw (with two mono PAMs), to one more like Lincoln Center, in NYC (with the DSC-1). It was most evident on Elvis Presley 45 rpm records from Sun, although other records from Sun, those from Sun Ra released on El Saturn, were used during the audition.

Much ink was spilled over the issue, back and forth. Gillian Gersh, at Audio Review, counted the knobs on the two preamps, and concluded that the two PAMs with the DSC-1 was better, because it had more knobs and switches, for the money. Using his Bose 901s as a reference, Gillian stated that he couldn't hear any difference between the two. High Infidelity technical editor, Larry Blind, agreed.

The most promising theory arguing for the effect was probably that coming out of Helsinki, from Hattie Lotala, and her stateside colleague, Enid Dumley, who suggested that the problem was one they called Transient Interconnectivity Distortion, which happened when two circuits were passively bolted to (but not electrically connected to) a single metal chassis. But they concluded it was impossible to detect under 'steady-state' conditions, and in fact they didn't have any definitive way to 'measure' the effect, one way or the other.

For her part, Dumley suggested that it could have something to do with 'stray' magnetic fields, and after consulting with magnetic field authority Bob Larder, theorized that wrapping common household electrical motors with Reynolds wrap, might help. She then proceeded to wrap her refrigerator in aluminum foil, and reported that although this improved the music's low-level plankton, once it was all enclosed in tin foil it was impossible to open her refrigerator door to get out beers. However it was not a total loss, because she had enough left on the roll to make herself a nice little hat, which she was quite proud of, and got her a lot of admiring looks whenever she went out of doors, shopping.

The issue was finally solved when Clark Levinsun teamed up with John Hurl, to create the CJ-6abc preamplifier, consisting of not only two separate unconnected chassis, but two separate power supplies. The fact that it cost more money than God had in his checkbook was of little moment to true audiophiles, for whom money is always secondary to audio nirvana.

However, science never stops, and research is still on-going. Recently, Audiobest company found that replacing the CJ-6abc power cable with two of their Constant Current Sharknado Typhoon power cords resulted in an even greater sonic improvement. Saul McGowen made further progress by building a dedicated power conditioner (designed by Baskin Queen, with FET output, and tube input stage) for the CJ-6abc, but since these are mono preamps, you need two of them for best results.

Finally, scuttlebutt from the field has it that some guy named Amir, at an operation called ASR, is going to do some independent investigation, and maybe post a Yoo Hoo video, in order to finally get to the bottom of the problem. If it is a problem at all. Expect good news soon.

PS: apologies to the folks at Gryphon, who appear to have made a pretty nice preamp (if black and gold are your thing).
An utterly brilliant piss take!
You sir/madam are a genius!
 

Koeitje

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You assume well. But this is true in theory, the reality is different. Try changing preamps in your chain (perhaps borrowed from some friends) and listen to the result. Some may be indistinguishable; with others there will be more substantial differences.
Or there are simply differences in gain.
 
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