Well, there is working regulator now, confirmed with dmm. But same symptoms and not working. Pcb is starting to look like s**t because of resoldering 😀
Trimpot 0, altought it seems that it's position is irrelevant right now 🙂
Pin 1 is dot marked and 2 just next to it? Somethin like 1.2mV only there..
each THF chip is outputting ( at zero Iq) something as Ub/2 , which is 2V5, ref. to GND
so , you need to have something as that on both R16 and R17 , sides to THF chips
than that's summed through these two resistors and taken further through R15 and P1
RS is 1K6 , shunting optodiode
VR1 is there just in case , as optoled guardian , but not really necessary
all that easiest to check without mosfets connected to pcb
though , it's hard to invent any scenario what happened , if first 7805 was Dodo , pretty much nothing else could go south , except output mosfets , and even that mostly because you weren't monitoring Iq critically as it was needed
compare whatever you can think of , unpowered, with functional channel
I'm here , hope we'll figure out together what's wrong
so , you need to have something as that on both R16 and R17 , sides to THF chips
than that's summed through these two resistors and taken further through R15 and P1
RS is 1K6 , shunting optodiode
VR1 is there just in case , as optoled guardian , but not really necessary
all that easiest to check without mosfets connected to pcb
though , it's hard to invent any scenario what happened , if first 7805 was Dodo , pretty much nothing else could go south , except output mosfets , and even that mostly because you weren't monitoring Iq critically as it was needed
compare whatever you can think of , unpowered, with functional channel
I'm here , hope we'll figure out together what's wrong
trace with buzzer test ( so unpowered) , have you 5V to THF chips ?
also check is there GND to chips
if both yes , we have scenario - 7805 goes berserk , dodo THF chips because of overvoltage , dodo 7805
also check is there GND to chips
if both yes , we have scenario - 7805 goes berserk , dodo THF chips because of overvoltage , dodo 7805
send me an e-mail , we'll solve that
unfortunately , not today, not tomorrow , as you would like it most ....... and me too
unfortunately , not today, not tomorrow , as you would like it most ....... and me too
Nice pictures Zen Mod, I need to pull myself together and finish my Sissies. Havent had the heart yet to split my M2 apart and reuse supply and chassis. My F6 and M2 are great amps, so I look forward to hear the Sissies and the SIT flavour.
up and running today
hey ZM i got my M25 with Edcores playing music today! Really took my time with this build, especially the biasing as it relates to temperature stability. I learned a lesson from my last rushed build and got burned (pun intended) when the newly rebuilt F5T sounded sublime for a couple of weeks until the first hot summer day here in New England.
I want to say thank you so much for putting this together; it's better sounding than i had hoped (those were high hopes too).
Coming from an F5Tv2, i find the M25 more detailed and at the same time more relaxed.
i think the noise floor may be so incredibly low as to reveal microdetail that was (could it be?) masked by the F5T on my ~105 dB sensitive La Scala 2s.
The highs are a little softer which is appreciated on horn speakers. Most striking is the enhanced sense of instrument and orchestral solidity and separation from the M25. F5T is crazy fast, neutral almost to a fault and feels as if it has slightly more headroom in comparison.
F5T=Cameron Fry's house next to M25's playboy mansion (in a classy way).
M25 feels very liquid; makes me think of my old Mcintosh MC30's but with breathtakingly low distortion and noise. The noise and distortion are part of the charm with the old tube amps. The M25 doesn't quite have that spooky hyper-realism the MC30's are known for. M25 has a cooler character, leaning a towards but still sitting on the warm side of neutral.
Also, the M25 is silent as a frikin tomb on my wicked sensitive speakers.
It's only been a couple of hours listening so far and these impressions should be taken with a shaker of salt.
I'll post some porn tomorrow and also share my experience biasing this thing. It's been a long day and i'm falling asleep.
Thanks again ZM and everyone who contributed to this forum, your generosity of time and knowledge in the support of this hobby is humbly appreciated.
hey ZM i got my M25 with Edcores playing music today! Really took my time with this build, especially the biasing as it relates to temperature stability. I learned a lesson from my last rushed build and got burned (pun intended) when the newly rebuilt F5T sounded sublime for a couple of weeks until the first hot summer day here in New England.
I want to say thank you so much for putting this together; it's better sounding than i had hoped (those were high hopes too).
Coming from an F5Tv2, i find the M25 more detailed and at the same time more relaxed.
i think the noise floor may be so incredibly low as to reveal microdetail that was (could it be?) masked by the F5T on my ~105 dB sensitive La Scala 2s.
The highs are a little softer which is appreciated on horn speakers. Most striking is the enhanced sense of instrument and orchestral solidity and separation from the M25. F5T is crazy fast, neutral almost to a fault and feels as if it has slightly more headroom in comparison.
F5T=Cameron Fry's house next to M25's playboy mansion (in a classy way).
M25 feels very liquid; makes me think of my old Mcintosh MC30's but with breathtakingly low distortion and noise. The noise and distortion are part of the charm with the old tube amps. The M25 doesn't quite have that spooky hyper-realism the MC30's are known for. M25 has a cooler character, leaning a towards but still sitting on the warm side of neutral.
Also, the M25 is silent as a frikin tomb on my wicked sensitive speakers.
It's only been a couple of hours listening so far and these impressions should be taken with a shaker of salt.
I'll post some porn tomorrow and also share my experience biasing this thing. It's been a long day and i'm falling asleep.
Thanks again ZM and everyone who contributed to this forum, your generosity of time and knowledge in the support of this hobby is humbly appreciated.
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Will the SissySIT fit in a DIYA Deluxe 4U 300 chassis?
Also, is there any significant benefits to running dual power supplies?
Also, is there any significant benefits to running dual power supplies?
The 4U 300 probably does not have enough heat sink. ZM recommends the 4U 400 - see post #406.
ZM also recommends dual mono - see post #113. He has also mentioned it in other posts.
ZM also recommends dual mono - see post #113. He has also mentioned it in other posts.