Difficult to say without seeing the schematic.
But if the supply voltage is some 250 V and tube halves are connected parallel, the suitable load impedance is about 8k.
Most suitable transformer would be this:
EDCOR - GXSE10-8K
or
EDCOR - GXSE15-8K
By the way, how did you deduce that the reason for missing "high notes" is OPT ?
But if the supply voltage is some 250 V and tube halves are connected parallel, the suitable load impedance is about 8k.
Most suitable transformer would be this:
EDCOR - GXSE10-8K
or
EDCOR - GXSE15-8K
By the way, how did you deduce that the reason for missing "high notes" is OPT ?
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The Hammond 125ese have 32 ohms output, suitable for headphones. Do you use the amp for this or connected to speakers?
I use 2.5k load impedance, black and white line sounds best, speaker is Jensen p12s. Edcor has two series xse and gsxe, i don´t know what to buy, 25 watt xse or 15 watt gsxe. Load impedance 2.5k or 3K? I don´t use tweeter so high frequency is little lost. I don´t hear cymbals.
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in this thread post#5 you said you don't use a tweeter,. Try a tweeter.
check post #10 here, there's a graph of the Hammond 125ESE
SE EL34 schematic HELP: from two 6SL7's to One?
Hammond 125 ESE amps for 2018 10 5 post
Edcors are suppose to be good, lots of people use them.
Could someone post what commercial products use Edcor?
TIA
-Chris
check post #10 here, there's a graph of the Hammond 125ESE
SE EL34 schematic HELP: from two 6SL7's to One?
Hammond 125 ESE amps for 2018 10 5 post
Edcors are suppose to be good, lots of people use them.
Could someone post what commercial products use Edcor?
TIA
-Chris
from post#2, Edcors- check the specs, if they are better to you(or Tango, etc), go buy them, install them and see if you are happy with them.
As several others have said: I don't think a different output transformer will solve the problem you are having.
Isn't the Jensen P12S a guitar amp or PA speaker? What's the response curve of that speaker?
Can you describe exactly how you have connected the Hammond transformer to the amp (primary) and speakers? The load that the output tube 'sees' depends on both connections.
Also, posting the schematic of the amp and the Hammond windings diagram will help.
BTW, the YouTube video had 'nothing but treble' in my headphones here - a problem with trying to show sound response in a YouTube video.
Jensen p12s is extrended range speaker from 50´s, i don´t know response curve. Hammond transformer has just brown and blue primar connection, speakers are connected white and black wire. I don´t have schematics yet, it is single ended amp. The amplifier has more than enough bass, it is triode amp.
This depends on the source feeding the OPT. A parallel connected 6N6P has relatively low output impedance.
Therefore I am quite sure the high end response is far more than 15 kHz.
Again, how did you locate that the lack of "high notes" is due to the OPT ?
Attachments
well, to be fair to Hammond, they say this about the 125ese:
Frequency response: 100 Hz. - 15 Khz at full rated power (+/- 1db max. - ref. 1 Khz). For full frequency response (20 Hz. to 20 Khz.) - see our 1627-1642 series.
Personally, I can't hear 15kHz test signal anymore, so am thinking that if you are missing the "higher frequencies" then maybe look at your circuit.
Especially the power supply (hint.. hint.. hint..) Please post your circuit (all of it), since the yootoob video tells very little.
Best regards
Ian
p.s. Toroidy is really close to you in Poland, and if you feel the urge, Lundahl is also an option. I would look into Toroidy though...
Frequency response: 100 Hz. - 15 Khz at full rated power (+/- 1db max. - ref. 1 Khz). For full frequency response (20 Hz. to 20 Khz.) - see our 1627-1642 series.
Personally, I can't hear 15kHz test signal anymore, so am thinking that if you are missing the "higher frequencies" then maybe look at your circuit.
Especially the power supply (hint.. hint.. hint..) Please post your circuit (all of it), since the yootoob video tells very little.
Best regards
Ian
p.s. Toroidy is really close to you in Poland, and if you feel the urge, Lundahl is also an option. I would look into Toroidy though...
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Cymbals are generally speaking not that high.
Hi-Hats are usually between 300-3000 Hz dominant frequencies, and can extend up to 10-17k Hz for crispness, “air” and sparkle. The “shhhhhhhhh” sound is usually found at the 2-3k Hz range
See? if you are not hearing cymbals then I think maybe you are experiencing some roll-off much below 15kHz.
Also, the primary impedance of your OPT's is not really good. Your PSE 6N6P load line will be crazy steep... Better go for 5k (black to yellow) or even better 10k (black to green) for your 8 ohm speakers.
Edit: I see this was already suggested by Artsalo.
The 6N6Pi should have a plate resistance, rp, of approximately 1,800 Ohms.
That should drive the distributed capacitance of most transformers fairly well.
The leakage reactance of the transformer may be another issue.
1,800 ohms rp driving 2500 Ohm primary (in the case of how you have the transformer wired), does not give a good damping factor.
How about posting a schematic of the amp?
How about some other item details:
A grid stopper resistance that is too large, versus the miller capacitance?
A high capacitance shielded cable that is too long?
A shielded cable that comes off of the wiper of a very high resistance volume control (i.e 500k Ohms)?
The signal source output impedance, and long shielded cable from source to amplifier?
etc.
That should drive the distributed capacitance of most transformers fairly well.
The leakage reactance of the transformer may be another issue.
1,800 ohms rp driving 2500 Ohm primary (in the case of how you have the transformer wired), does not give a good damping factor.
How about posting a schematic of the amp?
How about some other item details:
A grid stopper resistance that is too large, versus the miller capacitance?
A high capacitance shielded cable that is too long?
A shielded cable that comes off of the wiper of a very high resistance volume control (i.e 500k Ohms)?
The signal source output impedance, and long shielded cable from source to amplifier?
etc.
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