rainton
Well-known member
Hey guys,
I'm just about to do a Pultec EQP1-A all p2p and as close to the original as possible.
Even though I already found most of the original switches, knobs, input tranny etc...
...I realized how much of an unobtanium the Triad HS29 and the Peerless S217D are nowadays.
I know that Sowter makes some trannys for use in a Pultec but I discovered that their HS29 replacement has a totally different impedance compared to the original.
5K/20k to 80K/20K in the original
2.5K to 10K in the Sowter replacement??
Doesn't the difference in impedance make a difference in sound
And then I figured, why not rather use a Triad HS27 which has the same impedance as the HS29, but a ratio of 1:1.72 compared to 1:2 of the original?
Or - even easier available the Triad HS23? It has an impedance of 15K to 110K (but still closer than the Sowter replacement) and a ratio of 1 : 2.7 instead of 1:2
What would I need to change in the circuit if I wanted to use the HS23 instead of the HS29?
Having a ratio of 1 : 2.7 the signal would hit the amp circuit at a slightly higher level and I would need to compensate for that, right?
Any suggestions?
What about the difference in impedance?
Thanks for any advice!
Martin
I'm just about to do a Pultec EQP1-A all p2p and as close to the original as possible.
Even though I already found most of the original switches, knobs, input tranny etc...
...I realized how much of an unobtanium the Triad HS29 and the Peerless S217D are nowadays.
I know that Sowter makes some trannys for use in a Pultec but I discovered that their HS29 replacement has a totally different impedance compared to the original.
5K/20k to 80K/20K in the original
2.5K to 10K in the Sowter replacement??
Doesn't the difference in impedance make a difference in sound
And then I figured, why not rather use a Triad HS27 which has the same impedance as the HS29, but a ratio of 1:1.72 compared to 1:2 of the original?
Or - even easier available the Triad HS23? It has an impedance of 15K to 110K (but still closer than the Sowter replacement) and a ratio of 1 : 2.7 instead of 1:2
What would I need to change in the circuit if I wanted to use the HS23 instead of the HS29?
Having a ratio of 1 : 2.7 the signal would hit the amp circuit at a slightly higher level and I would need to compensate for that, right?
Any suggestions?
What about the difference in impedance?
Thanks for any advice!
Martin