I finally got the chance to hear these amps in my main system. They are great. My reference is a Hegel H360 integrated. I am using a Audio GD Master 9 as a preamp into the pair of Folsoms.
I think they are a bit better than the Hegel throughout the midrange but this maybe a preference of mine. The Hegel is warmer but still detailed. The Folsoms are not exactly 'not' warm they just seem to be clearer in the midrange, the Hegel a little fuzzy in certain places. I give the edge in treble to the Folsoms. They seem to be a hair more extended. Soundstage is phenomenal on both. I only listened for about a hour so I need more time with them. I prefer the Folsoms so far.
I own GR research Super 7s so I can't evaluate bass because my speaker have powered subs for everything below 200 hz.
I think the 32db gain on these amps is a bit high though. I prefer the mid twenties. I emailed Jeremy a while back and asked how to reduce the gain and all I had to do is add a resistor in parallel with another. I have only gotten around to doing this on one of the amps. DC offset did not change much at all and I didn't notice any added heat. According to Jeremy the amp should now be about 24db. I will test it out further over the weekend. On my test speaker the output definately seemed lower so I am happy.
I think they are a bit better than the Hegel throughout the midrange but this maybe a preference of mine. The Hegel is warmer but still detailed. The Folsoms are not exactly 'not' warm they just seem to be clearer in the midrange, the Hegel a little fuzzy in certain places. I give the edge in treble to the Folsoms. They seem to be a hair more extended. Soundstage is phenomenal on both. I only listened for about a hour so I need more time with them. I prefer the Folsoms so far.
I own GR research Super 7s so I can't evaluate bass because my speaker have powered subs for everything below 200 hz.
I think the 32db gain on these amps is a bit high though. I prefer the mid twenties. I emailed Jeremy a while back and asked how to reduce the gain and all I had to do is add a resistor in parallel with another. I have only gotten around to doing this on one of the amps. DC offset did not change much at all and I didn't notice any added heat. According to Jeremy the amp should now be about 24db. I will test it out further over the weekend. On my test speaker the output definately seemed lower so I am happy.
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I finished lowering the gain on the second amp and I put them both back in my main system. Lowering the gain worked wonders as I now have alot more room on my volume dial to play with.
These things are phenomenal. Stunning clarity and as a result the deepest soundstage I have heard on any amp I have either owned or borrowed recently. Soundstage height and width are equal to the best I have had in my system so far, the Cherry Maraschinos, but these things ace the Cherry's in every other measure. The Folsom do everything better than the Hegel H360 as well - but the caveat here is that my speakers are 97db sensitivity. The Hegel likely pulls ahead with harder to drive speakers. I borrowed a friend's Liberty B2B-100 amp late last year and I also found that amp generally better than the Hegel. The liberty sounds like a slightly less clear, more powerful version of the Folsoms. The Folsoms also sound a bit quicker. I would have purchased the Liberty last year had it not been for its high gain (32db IIRC) just way too much for my 97 db speakers given that the B2B pumps out 110 watts.
Now I have to build a permanent home for them. I wanted monoblocks for a while but I think I am just going to put them in one chassis. I havent made a final decision.
Recent amps I have had or heard in my system are the Cherry Maraschinos, Hegel H200, Liberty B2B-100, Schiit Aegir. Current system is Hegel H360, Schiit Yggdrasil, Audio GD Master 9, GR research Super 7.
Unfinished amps. The extra circuit boards you see is the Neurochrome Gaurdian 86 for speaker protection. I am thinking about adding a soft start circuit as well.
Folsom amps being tested
Current audio stack.
(Untitled)
PS: I know the heatsinks are small - this isnt the permanent stop for the amps. I bought an extra quad of the amp chips just in case I screw them up when I am desolderng them to mount to the chassis heatsink later.
These things are phenomenal. Stunning clarity and as a result the deepest soundstage I have heard on any amp I have either owned or borrowed recently. Soundstage height and width are equal to the best I have had in my system so far, the Cherry Maraschinos, but these things ace the Cherry's in every other measure. The Folsom do everything better than the Hegel H360 as well - but the caveat here is that my speakers are 97db sensitivity. The Hegel likely pulls ahead with harder to drive speakers. I borrowed a friend's Liberty B2B-100 amp late last year and I also found that amp generally better than the Hegel. The liberty sounds like a slightly less clear, more powerful version of the Folsoms. The Folsoms also sound a bit quicker. I would have purchased the Liberty last year had it not been for its high gain (32db IIRC) just way too much for my 97 db speakers given that the B2B pumps out 110 watts.
Now I have to build a permanent home for them. I wanted monoblocks for a while but I think I am just going to put them in one chassis. I havent made a final decision.
Recent amps I have had or heard in my system are the Cherry Maraschinos, Hegel H200, Liberty B2B-100, Schiit Aegir. Current system is Hegel H360, Schiit Yggdrasil, Audio GD Master 9, GR research Super 7.
Unfinished amps. The extra circuit boards you see is the Neurochrome Gaurdian 86 for speaker protection. I am thinking about adding a soft start circuit as well.
Folsom amps being tested
Current audio stack.
(Untitled)
PS: I know the heatsinks are small - this isnt the permanent stop for the amps. I bought an extra quad of the amp chips just in case I screw them up when I am desolderng them to mount to the chassis heatsink later.
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I've tested many amps with Tom's protection and without and I can assure you it is really transparent. I haven't seen a difference in sound. As you probably know Tom, he's an amazing engineer and everything has been measured to not add noise. Mosfets protection when well done is light years ahead of relays.
But people are free to not use them...
Do
But people are free to not use them...
Do
Would you or Jeremy mind sharing where/how to adjust the gain? I have a feeling it might be helpful to at least test when I get back to finishing mine up. Thanks!
This is an untested modification by us. It was suggested on a trial basis.
I would know that ciphercomplete's preamp has a fair amount of gain, and options for a lot of gain. It shouldn't be necessary for most.
Yeah I have an older Audio GD Master 9 with 14db gain. I think the new one is even higher. I plan on re-acquiring the master 1 as it is only 10db gain. I like to use the Master 9 for headphones primarily.
But even when I had the Master 1 two years ago and Wyred 4 Sound stp se a few years back, I still prefered amps with lower gain.
But even when I had the Master 1 two years ago and Wyred 4 Sound stp se a few years back, I still prefered amps with lower gain.
Hi all, I am new to these forums, but have read through this thread with great interest in looking to build a couple mono blocks.
So many awesome implementations within this group.
I have been in contact with Jeremy, but unfortunately he had sold out of the 7293's.
Just wondering if anyone has two empty 7293 boards they might want to sell, or if there is a list somewhere I can add my name to for the next buy.
Thanks,
Jody
So many awesome implementations within this group.
I have been in contact with Jeremy, but unfortunately he had sold out of the 7293's.
Just wondering if anyone has two empty 7293 boards they might want to sell, or if there is a list somewhere I can add my name to for the next buy.
Thanks,
Jody
Hi guys,
I'm a newbie but dreaming of assembing this one.. some day. I haven't seen the BOM, and I'm just trying to figure out approximate budget of that build.
With no super expensive fancy caps.. just a kind of decent build, everything included (trans, chasis), no shipping costs.
What would be the estimations?..
Thanks!
I'm a newbie but dreaming of assembing this one.. some day. I haven't seen the BOM, and I'm just trying to figure out approximate budget of that build.
With no super expensive fancy caps.. just a kind of decent build, everything included (trans, chasis), no shipping costs.
What would be the estimations?..
Thanks!
For dual mono - shipping and taxes not included
2 - AS-2225 - 200VA 25V Transformers - $65
LED Lamps - $9
Solar Cells - $15
Passive components (Mouser) - ~$230
Chassis - ~$150
Figure another ~$50 for assorted bits, even more for boutique caps.
EC7293+G4LEDR PCB $45ea (you'll need 2, to make a stereo amp) = $90
DualPole PSU PCB $40ea - also 2 for dual mono = $80