[hilde45]

Hi Frank, I have Salk's SS 6M stand mounts. 8ohm, 87 db. I have a Quicksilver Line stage I really like. I am considering one of your solid state power amps to create a nice hybrid tube/SS combo for the Salks. Which of your amps would match well with this preamp and speaker? I'm thinking about The Vision SET 120? The Vision SET 400? Would something else jump out as a good match?

Specs on QS Linestage
Gain 18 db
Input Impedance 100 Kohm, 20 Hz-20 KHz
Output Impedance 100 ohms, 20 Hz-20 KHz
Output Polarity inverted
Maximum Input 30 volts RMS, 20 Hz-20 KHz
Maximum Output 60 volts RMS, 20 Hz-20 KHz

Thank you and Happy Holidays! hilde45

[JackD]

hilde45

I am using the latest version of the Don Sachs Model 2 which is also 18db gain along with the SET 400 and due to the SET's higher input sensitivity, which Frank quoted to me as 2.4 volts, it is a great match.  The speaker used with this pairing is the Reynaud Abscisse Jubilee which has sensitivity specs pretty much the same as your Salk's.  At Frank says the sound of the two is basically the same it will come down to how much reserve power you want to have for your rooms size and music preferences as both will likely do the job just fine.   

[aln]

I would recommend the 400 as well.  Once you buy it - you are done.  Enjoy!

[hilde45]

Thanks for the advice, folks! I'm balking a little at the fact that the 400 is more than 2x the price of the 120. Wondering if my medium sized room (2800 cu. ft) needs the extra horsepower or if there's a qualitative difference with the 400?

[aln]

There is a real difference in listening to a 60 watt per channel amplifier and a 200 watt per channel amplifier.  Dynamic range will be increased.  Again-good luck but with Franks return policy what do you have to lose?

[JackD]

You can always start with the 120 and with the 30 day return window if you feel it's not enough or just decide you want more just swap up with him. 

[decooney]

While AVA Frank replied to me over the summer indicating the SET 120 and SET 400 effectively have the same circuit design and the same Exicon MOSFETs (and "sound the same"), (with fewer of the same MOSFETS on the 120) I'd like to see an internal photo shot of the 400 to compare torroidal transformer sizes and quantity of caps.  The SET 400 is 8lbs heavier by shipping weight, and we know the added mosfets don't weigh that much.  Yes, the chassis and larger footprint on the 400, more metal top half of chassis, maybe larger heat sinks..., but wonder if there are different size or quantify of transformers in each of these size amps. 

My dilemma deciding between the two with 87db sensitivity speakers would be LOW listening levels, not just "watts". Would the SET 400 have more drive compared to the SET 120 at lower listening levels. ???  Went through this same scenario with several former B&K MOSFET amps, 50w, 100w, 150w, 220w with the same mosfets and circuits and the yet 220w Dual Mono amp with dual torroidal transformers was significantly better, with much better drive at low volume listening levels with my own 87db Totem Acoustic Signature speakers at the time.  And, 38lbs for the SET 400 seems kinda light weight comparatively to my former 200+ class A/AB amps all closer to 79 to 87lbs. Maybe "Less is more" in the circuit so to speak, would have to demo both to hear it first hand. In my case, even with 92db speakers I'd probably end up with the SET 400, but I'd have to demo both back to back to be sure either way. 

hilde45,
I'd also check with Jim Salk and ask him too.  He'd know for sure which would be better with your particular Salk monitors.  Fun project.  Good Luck.   

[decooney]

Update: maybe part of the answer here on weight difference, former SET 400 for sale last Jan 2020 right here on Audiocircle.  Much bigger external Heat Sinks, maybe bigger transformers inside too?  Photos in this former listing to see back side views.  Looks like "JackD" here was the lucky buyer too, Nice!

https://www.audiocircle.com/index.php?topic=167214.0

[JackD]

audiojem(Jeff) just sold a silver one for the same price last week.

[srb]

Class AB amplifiers run in Class A for the first watt (or first few watts or first 10 watts, etc.) depending on the circuit design and bias levels before transitioning to class A/B.

With two amplifiers of different power output, but particularly of the same design and model lineup, the more powerful one will generally have more Class A watts before the transition.

Perhaps this is a contributing factor in some users preferring the larger amplifier over the smaller one for low level listening?

[Tone Depth]

Trust what Frank is saying about his amps. Jim Salk split from exhibiting with Frank a number of years ago, before the SET amp designs were developed.

While AVA Frank replied to me over the summer indicating the SET 120 and SET 400 effectively have the same circuit design and the same Exicon MOSFETs (and "sound the same"), (with fewer of the same MOSFETS on the 120) I'd like to see an internal photo shot of the 400 to compare torroidal transformer sizes and quantity of caps.  The SET 400 is 8lbs heavier by shipping weight, and we know the added mosfets don't weigh that much.  Yes, the chassis and larger footprint on the 400, more metal top half of chassis, maybe larger heat sinks..., but wonder if there are different size or quantify of transformers in each of these size amps. 

My dilemma deciding between the two with 87db sensitivity speakers would be LOW listening levels, not just "watts". Would the SET 400 have more drive compared to the SET 120 at lower listening levels. ???  Went through this same scenario with several former B&K MOSFET amps, 50w, 100w, 150w, 220w with the same mosfets and circuits and the yet 220w Dual Mono amp with dual torroidal transformers was significantly better, with much better drive at low volume listening levels with my own 87db Totem Acoustic Signature speakers at the time.  And, 38lbs for the SET 400 seems kinda light weight comparatively to my former 200+ class A/AB amps all closer to 79 to 87lbs. Maybe "Less is more" in the circuit so to speak, would have to demo both to hear it first hand. In my case, even with 92db speakers I'd probably end up with the SET 400, but I'd have to demo both back to back to be sure either way. 

hilde45,
I'd also check with Jim Salk and ask him too.  He'd know for sure which would be better with your particular Salk monitors.  Fun project.  Good Luck.

[decooney]

@Tone Depth

Trust what Frank is saying about his amps. Jim Salk split from exhibiting with Frank a number of years ago, before the SET amp designs were developed.

Would have to demo both for sure.  Been building speakers as long as Jim Salk or longer, and demo'd enough amps to know it can be hit or miss.  Grew up around Threshold, PASS, and Coda. While I don't need another amp myself, have several friends and colleagues looking for a second amp to alternate between mono tube amps in the summer. A new SET 400 might work, about the same cost as what it takes to properly rebuild and upgrade a Threshold or pick up a FW SIT3, low power amps with plenty of grunt for reasonably efficient speakers.       

[decooney]

...

[I.Greyhound Fan]

Hi Frank, I have Salk's SS 6M stand mounts. 8ohm, 87 db. I have a Quicksilver Line stage I really like. I am considering one of your solid state power amps to create a nice hybrid tube/SS combo for the Salks. Which of your amps would match well with this preamp and speaker? I'm thinking about The Vision SET 120? The Vision SET 400? Would something else jump out as a good match?

Specs on QS Linestage
Gain 18 db
Input Impedance 100 Kohm, 20 Hz-20 KHz
Output Impedance 100 ohms, 20 Hz-20 KHz
Output Polarity inverted
Maximum Input 30 volts RMS, 20 Hz-20 KHz
Maximum Output 60 volts RMS, 20 Hz-20 KHz

Thank you and Happy Holidays! hilde45

Give Frank a call.

[hilde45]

Thanks. I'll do that. I wanted to give him a chance to answer a kind of general question on his forum in case others have the same question, to save him time.

[JackD]

I expect he'll answer on Monday or reach out to you.

[I.Greyhound Fan]

I reviewed both the SET 120 and 400.  I preferred the 400 due to its extra power and dynamics.  However, both sound great and similar.  My reviews can be found on the AVA circle.  The SET 400 had no trouble driving my 4 ohm 86db Magnepan 1.6's to very loud levels.

[decooney]

I reviewed both the SET 120 and 400.  I preferred the 400 due to its extra power and dynamics.  However, both sound great and similar.  My reviews can be found on the AVA circle.  The SET 400 had no trouble driving my 4 ohm 86db Magnepan 1.6's to very loud levels.

Hello @I.Greyhound Fan,
Reading your other posts and reviews here on Audio Circle about the AVA SET 400, a few variables came to mind including using XLR adapters, Belden 8402 interconnects used, a BAT preamplifier used, and I thought a mention of using BH player software at one point.  i.e. ..."less depth to soundstage"..."compared to the PASS X250". 

Eventually were you able to evaluate the SET 400 or SET 120 amp with an AVA SET 120 Control preamp or without any XLR/SE adapters in the cable signal path?

 

[I.Greyhound Fan]

Hello @I.Greyhound Fan,
Reading your other posts and reviews here on Audio Circle about the AVA SET 400, a few variables came to mind including using XLR adapters, Belden 8402 interconnects used, a BAT preamplifier used, and I thought a mention of using BH player software at one point.  i.e. ..."less depth to soundstage"..."compared to the PASS X250". 

Eventually were you able to evaluate the SET 400 or SET 120 amp with an AVA SET 120 Control preamp or without any XLR/SE adapters in the cable signal path?

The xlr adapters do not change the sound except that you lose 6db in volume so going from XLR to single ended so you need to turn the volume up.  The SET amps are single ended only and my BAT is XLR only.  When I had a Pass preamp that had RCA and XLR in/outs I compared them and there was very little difference except for volume.

I heard both amps at Franks with his preamp, probably the FET Valve CF.

The Pass did have a slightly deeper sound stage but the SET amps had deep sound stages but the Pass was  a little better.   The SET amps had sweeter midranges.  But we are comparing a $7000 Pass amp to the SET amps.  The SET's held their own.

[decooney]

@I.Greyhound, appreciate the update and explanation. Makes sense after reading the R vs. SET model comments in other threads too.     

A colleague was asking if I'd go ahead and evaluate the SET amp a while back, but I think he moved on to something else. Was still kinda curious to evaluate it.

The prior plan was to pair up either the SET 120 or 400 amps up with my personal upgraded Triode 6SN7 tube preamplifier, with high quality OCC singled ended RCA cables, and my own R-2R Ladder Tube DAC.  I've tried this setup with other Class A/AB MOSFET based solid state and various tube amps with very respectable results. The goal was to see how much can be achieved with these lower cost ava value amplifiers; and to help out a few friends asking and trying to decide.  I noted your prior evaluations the past few years of the AVA and PASS amps, along the same lines of interest - thanks for your eval notes over time.