EL 34 thoughts ?

[tonyg88]

El34 is the next tube i am interested in.... I'd like to compare it a 7591 amp

 

[Blackdog61]

I like the honest direct ELECTRO HARMONIX 6CA7, not a fan of the "tube sound" filter effects of typical EL34.

They are certainly different. When using vintage speakers such as the AR 4X and Rectilinears, I preferred the EH tubes. The Chinese 34s are better with the Canton monitors which are very clear and on the analytical side.

 

[Lavane]

I like the honest direct ELECTRO HARMONIX 6CA7, not a fan of the "tube sound" filter effects of typical EL34.

I'm still liking the EH 6CA7's in my ST-70. Before using them I didn't care for the 12BH7 for the voltage gain stage with other output tubes I used.
But the 12BH7 sounds real good with the 6CA7's.

 

[Pio1980]

My experience with these has been only with amps with tapped screen (Ultra-Linear) p/p output stages. Do the same differences come across in amps with different configurations, pentode, triode, SE, ect?

 

[Blackdog61]

I tried them with the ST-70 strapped for triode and it was terrible. The EL34s sounded good that way but it’s running in UL.

 

[Lavane]

My experience with these has been only with amps with tapped screen (Ultra-Linear) p/p output stages. Do the same differences come across in amps with different configurations, pentode, triode, SE, ect?

I don't care for the sound of triode strapped. The EH-6CA7's didn't sound any better than the other output tubes sounded when triode strapped. Ive even thought about removing the switches on my ST-70.

 

[Pio1980]

I don't care for the sound of triode strapped. The EH-6CA7's didn't sound any better than the other output tubes sounded when triode strapped. Ive even thought about removing the switches on my ST-70.

I'm running the OEM circuit with the Vintage Electron 6CG8 board and adjustable splitter balance bias control added, solid state rectifier.
Dave Gillespie's thread on this amp persuaded me to stick with the oem Laurent Dyna driver and quit seeking Mac tube amps. The thread on the half-dead Mac 225 pretty much sealed that deal, and the Marantz 8 went to storage.

 

[JohnT123]

I think those EH 6CA7 tubes are the real deal. I fix a lot of vintage guitar amps and they are the only thing I use in old Hiwatts. Regular EL34 tubes are just too soft for those amps. I used them in my ST-70 and loved them. Sometimes cheaper is better. I'm the same way with KT66 tubes. The Shuguang tubes are the cheapest but they seem to be the closest in look and sound to my vintage GEC tubes.

 

[Lavane]

I think those EH 6CA7 tubes are the real deal. I fix a lot of vintage guitar amps and they are the only thing I use in old Hiwatts. Regular EL34 tubes are just too soft for those amps. I used them in my ST-70 and loved them. Sometimes cheaper is better. I'm the same way with KT66 tubes. The Shuguang tubes are the cheapest but they seem to be the closest in look and sound to my vintage GEC tubes.

I haven't tried KT-66's yet. I tried KT-88's in my ST-70, but the midrange didn't sound right. I tried several EL-34's and found them lacking a bit also. I ran JJ KT-77's for about 8 years and was happy with them. They sounded pretty well balanced over all. The 6CA7's are my favorite now. Better bottom end, good mirange and a nice top end sparkle without being harsh. I'm finishing up a modded Fender AA764 using a choke, 6x4 rectifier and 7 pin 6AQ5 instead of a 6V6. I've been looking for a schematic to use for a 6CA7 SE guitar amp.

 

[JohnT123]

If you change the output transformer this should do fine. You will of course fiddle with the bias resistor.

 

[drew_t]

I put a quad of the EH 6CA7s in my recently resuscitated HH Scott Model 272. I don’t have anything to compare them to, but they sound pretty good to me. One of the tubes was not well matched to the other three, but the vendor replaced it with one that was.