Thanks ZM!
I think this weekend I can power it up. I organised 3 alternative trafos because my Anteks are sitting in South Hackensack, NJ, since 6 days without any movement 🤔 Chassis is not arrived yet, so it will be an on-table test.
I think this weekend I can power it up. I organised 3 alternative trafos because my Anteks are sitting in South Hackensack, NJ, since 6 days without any movement 🤔 Chassis is not arrived yet, so it will be an on-table test.
if you connect it to system without proper box, and hear it ...... it'll be nightmare to disconnect it, for boxing purposes
should I send another one, to make transition less painful?

should I send another one, to make transition less painful?

Hi,
test setup is finished (Anteks and chassis under way but my patience is limited), so wish me luck
First power up follows after a short siesta 😀
test setup is finished (Anteks and chassis under way but my patience is limited), so wish me luck

First power up follows after a short siesta 😀
First power up done, no smoke
+/- 12v set, 20mv set (4x because balanced version), and 0vdc... well, there is something funny...
I can set 0vdc in both channels only for the + outputs (with P105 and P205). On the - outputs there is always 0vdc, no matter what I do with P103 and P203). But, and there is a big BUT, when I check the common point of R130 and LoadR- (I don't have this resistor), or R230 and LoadL-, there I can change the output vdc - but this is the same point as the output itself. I really don't understand it, because between the common point of R130 and LoadR- the resistance is 0 ohm... 🤔

+/- 12v set, 20mv set (4x because balanced version), and 0vdc... well, there is something funny...
I can set 0vdc in both channels only for the + outputs (with P105 and P205). On the - outputs there is always 0vdc, no matter what I do with P103 and P203). But, and there is a big BUT, when I check the common point of R130 and LoadR- (I don't have this resistor), or R230 and LoadL-, there I can change the output vdc - but this is the same point as the output itself. I really don't understand it, because between the common point of R130 and LoadR- the resistance is 0 ohm... 🤔

Stupid me 
I checked the circuit diagram and the pcb again... the - output points will only be activated in balanced mode where the input selector must set to a balanced input...
done, - output vdc set.
Listening follows 😍
Edit: thanks ZM 👍 as I wrote, stupid me

I checked the circuit diagram and the pcb again... the - output points will only be activated in balanced mode where the input selector must set to a balanced input...

Listening follows 😍
Edit: thanks ZM 👍 as I wrote, stupid me

do not forget, when doing final wiring, put tiny wire short between GND and Neg input pads, on each input you're wiring for SE
not so necessary, but better to have neg buffer input grounded, instead of flappin' in da Breeze
for your case, that would be inputs 1, 2, 3
so short between L1- and L1G
same for
L2- and L2G
L3- and L3G
R1- and R1G
R2- and R2G
R3- and R3G
not so necessary, but better to have neg buffer input grounded, instead of flappin' in da Breeze
for your case, that would be inputs 1, 2, 3
so short between L1- and L1G
same for
L2- and L2G
L3- and L3G
R1- and R1G
R2- and R2G
R3- and R3G
Thanks, will do so
First time in the system - lot of hum, even if the Pumpkin is not turned on. After turning it on even more hum.
There must be a ground loop, I think. I connected the mains ground to the "chassis bolt" (don't have a chassis but it seems to be the main gnd connection), and to the safety grounding point on the pcb.
Next try tomorrow.

First time in the system - lot of hum, even if the Pumpkin is not turned on. After turning it on even more hum.
There must be a ground loop, I think. I connected the mains ground to the "chassis bolt" (don't have a chassis but it seems to be the main gnd connection), and to the safety grounding point on the pcb.
Next try tomorrow.
it is normal that you have hum when Pumpkin is Off
Normal operation is - power On preamp, then power On amp and I don't care to include muting relays (when preamp is Off)
hope you did check function of all relays - that they are switching when needed etc.
also , do not forget jumpers at Turtle, you can start with 0db position
those EI xformers are most likely culprit - they're emanating huge magnetic field - practically 95% of print xformers are made with cost-cutting approach, so they're simply bad in that position - move them 1m away and you'll be good
I had one iteration of Iron Pumpkin with two EI xformers in case, proximity, and everything was silent - but those xformers were heavy artillery , bespoke pro quality
edit: considering that you now (in test setup) have common xformer for both channels, that means that channel GNDs are tied ...... while in proper arrangement everything is dual mono
feel free also to remove any connection to pcb Safety GND/Chassis - maybe you'll remove hum or decrease, that way
Normal operation is - power On preamp, then power On amp and I don't care to include muting relays (when preamp is Off)
hope you did check function of all relays - that they are switching when needed etc.
also , do not forget jumpers at Turtle, you can start with 0db position
those EI xformers are most likely culprit - they're emanating huge magnetic field - practically 95% of print xformers are made with cost-cutting approach, so they're simply bad in that position - move them 1m away and you'll be good
I had one iteration of Iron Pumpkin with two EI xformers in case, proximity, and everything was silent - but those xformers were heavy artillery , bespoke pro quality
edit: considering that you now (in test setup) have common xformer for both channels, that means that channel GNDs are tied ...... while in proper arrangement everything is dual mono
feel free also to remove any connection to pcb Safety GND/Chassis - maybe you'll remove hum or decrease, that way
Next round starts 😀
To the xformers, I don't have a common one for both channels, left you can see the two separated 2x15v xformers for the two channels and on the right side the 2x12v relais xformer.
To the xformers, I don't have a common one for both channels, left you can see the two separated 2x15v xformers for the two channels and on the right side the 2x12v relais xformer.
All relais are working; in the penultimate position there is a faint beeping coming from somewhere on the pcb (power amp off) 🤔
I could reduce the hum with removing the safety earth from the pcb and with some shielding of the xformers (but it is still here); with increasing the volume the hum gets quiter from the position 0 to 4, here almost disappears, but f.e. at position 5 there is more hum again.
First sounds were here 😍 but - even in the lowest position of the attenuator switch I have normal listening volume; I can increase the volume further, but I can't decrease it to zero (gain set at 0dB) 🤔
I could reduce the hum with removing the safety earth from the pcb and with some shielding of the xformers (but it is still here); with increasing the volume the hum gets quiter from the position 0 to 4, here almost disappears, but f.e. at position 5 there is more hum again.
First sounds were here 😍 but - even in the lowest position of the attenuator switch I have normal listening volume; I can increase the volume further, but I can't decrease it to zero (gain set at 0dB) 🤔
Turtle wiring is good, you connected proper wires framed in rectangle
confirm that you're having approx 24Vdc for relays, that regarding beeping, I can't predict what can be reason for
now, level - most attenuated position ( step 1 ) is -48db down; deliberately didn't made it as mute position
if you have normal listening level on step 1, you're in trouble regarding gain distribution of your system
what is your source- amplification line-up?
just in case, that being often cause of troubles with balanced - miss-wiring of XLR pins ( been there, doe that - being blind and looking from opposite sides sometimes )
Pin 1 - GND
Pin 2 - Hot Positive
Pin 3 - Hot Negative
applicable for both male and female XLRs
confirm that you're having approx 24Vdc for relays, that regarding beeping, I can't predict what can be reason for
now, level - most attenuated position ( step 1 ) is -48db down; deliberately didn't made it as mute position
if you have normal listening level on step 1, you're in trouble regarding gain distribution of your system
what is your source- amplification line-up?
just in case, that being often cause of troubles with balanced - miss-wiring of XLR pins ( been there, doe that - being blind and looking from opposite sides sometimes )
Pin 1 - GND
Pin 2 - Hot Positive
Pin 3 - Hot Negative
applicable for both male and female XLRs
Many thanks!
Connectors checked, everything is fine.
I use a Project StreamBox RS with an output voltage of 4v via xlr.
In the meantime I made some measurements. Between channel gnd and chassis bolt I have 5,3 ohms in both channels and 0 ohm between the two channel gnd's, so the NTC are parallelled... have to check why the two channel gnd's aren't separated 🤔
Will check the relais voltage now.
Many thanks for your help and patience
Connectors checked, everything is fine.
I use a Project StreamBox RS with an output voltage of 4v via xlr.
In the meantime I made some measurements. Between channel gnd and chassis bolt I have 5,3 ohms in both channels and 0 ohm between the two channel gnd's, so the NTC are parallelled... have to check why the two channel gnd's aren't separated 🤔
Will check the relais voltage now.
Many thanks for your help and patience

Checked everything and found a $%×=€£%%&^ short circuit in one of the xlr's, a hair thin wire.
Grounded the unsused inputs of the SE buffers.
The hum is very very quiet, one can hear it near the speakers - it will go with the donuts.
And - it sings, it sings beautiful 😍 It is unbelievable clear, detailed, with huge dynamics, great mids, crisp highs and deep and dry bass... the instruments are placed wide and deep on the stage. I'm speechless and get goosebumps
Many thanks for this, Mighty ZM
Grounded the unsused inputs of the SE buffers.
The hum is very very quiet, one can hear it near the speakers - it will go with the donuts.
And - it sings, it sings beautiful 😍 It is unbelievable clear, detailed, with huge dynamics, great mids, crisp highs and deep and dry bass... the instruments are placed wide and deep on the stage. I'm speechless and get goosebumps

Many thanks for this, Mighty ZM

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