I don't know jack about tubes or tube amp design. But I do know that KT120s and KT150s are capable of producing higher output power levels from some basic research I have done. Does anyone know of any kits or plans to build up monoblocks that can produce >150W @ 4Ω? I have too many projects going on right now to spend the time to teach myself tube amp design from the ground-up, so I'm looking for something that is like a "turn-key" type of kit/plan.
The 8340 doesn't really use KT120s and 150s to full advantage. The bias is set too low for these tubes. The output transformers in the 8340 won't support more than about 40 watts I'd estimate. The 8340 does sound lovely with Genalex (reissue) KT77s though.
S.
S.
it’s pretty safe to say that if you need 150 watts from a tube amplifier you are going to be looking at a parallel push-push topology running class AB in ultra linear mode. A power hungry beast like that is going to call for a big power supply so you are also probably going to want to split the amplifier in half and want mono blocks.
Whether or not it can provide that power to a 4 ohm load is entirely up to the quality of the output transformer and the impedance vs frequency deviation (from a nominal 4 ohms) of your bass driver. Don’t scimp on the OPT and you should be fine.
Whether or not it can provide that power to a 4 ohm load is entirely up to the quality of the output transformer and the impedance vs frequency deviation (from a nominal 4 ohms) of your bass driver. Don’t scimp on the OPT and you should be fine.
Last edited:
He was looking for a kit Steve that's the only one I could find---so far for those tubes , the original KT range were specially made for audio and had a good reputation .
Bob Latino M-125 mono blocks
125W into 4 ohms. Closest I can get to your power needs in kit form.
I’ve purchased from this outfit and have no complaints. I’ve installed an iteration of the driver board they are using (the one for the ST-70) and was very happy with the sound quality.
125W into 4 ohms. Closest I can get to your power needs in kit form.
I’ve purchased from this outfit and have no complaints. I’ve installed an iteration of the driver board they are using (the one for the ST-70) and was very happy with the sound quality.
Last edited:
Yes.
M125 from tubes4hifi.com is the closest you come. And it don't need
any unlinear kt120 or expensive kt150 either. Available as kit or built.
Thanks, that kit looks pretty good. Anyone know if that specific kit can produce more power output with other tubes? I'm gonna send them an email, but I thought I'd ask here in case someone has a definite answer as well.
No, it won't produce more power with other tubes. The limit is set by the B+
used and the primary impedance in the OT.
BTW you won't hear any difference in sound level between 120w and 150w,
it's much more significant what kind of speakers that is used.
Why 150W?
Do your speakers really need that much power?
I surely can't use those power levels, but that's not stopping me planning 200+ W/ch 😎
I won't be using expensive KT1xx on those: cheap TV tubes can deliver much more current.
Not a beginners project!
Voltage and current are very deadly at these levels.
Transformers need to be custom jobs.
Do your speakers really need that much power?
I surely can't use those power levels, but that's not stopping me planning 200+ W/ch 😎
I won't be using expensive KT1xx on those: cheap TV tubes can deliver much more current.
Not a beginners project!
Voltage and current are very deadly at these levels.
Transformers need to be custom jobs.
Bob said it would produce 8% more power with the KT120s.
I need lots of power to re-create what it sounds/feels like to be at a death/grindcore metal concert. I don't listen to whimpy girlie music.
►YouTube◄
▲That▲ needs to be played LOUD, like a mack truck is about to run you over. LOUD needs power. Speakers are about 90 dB/2.83V. Legacy Audio Calibres. Bass is boosted via a DSP low-shelf +12 dB from 100Hz downward. So YES, I do need that much power in the bass region.
You won't hear 8% difference in sound pressure, you need a doubling
of power to hear the difference.
If you won't a good amp kit with excellent build description, coupled with
excellent support then get yourself a pair of M125. Don't spend money
and trouble with "extras" or KT120 tubes, spare that to later when you have
used the amp for a while. Do what the manual says, no detours !
You can also use the right amp for the current mood as i do.
For lazy easy listening i use SE 20W tube amp and for those rough days i use 400W class-d.
Look for real tube power for GU81m PP amps up to 750W.
For lazy easy listening i use SE 20W tube amp and for those rough days i use 400W class-d.
Look for real tube power for GU81m PP amps up to 750W.
Last edited:
We can disagree there. I've played a lot with my DSP, and I can hear changes with less than 3 dB change in output, whether increase or decrease. I may not know about tube amp design, but I'm not new to audio. Far from it.
Thank you but I will do as I see fit with MY money. I don't plan to deviate from the plans/manual when/if I do end up getting them.
I'm more than fully aware of that. I have plenty of power on tap, if you look at the amp "rack" in the right corner of the picture/living room:
Unless that is a kit that I can outright readily by, it is of no use for me. Thank you.
Last edited:
Yes, you stated "I can hear changes with less than 3 dB change in output, whether increase or decrease."
A change of 8% is much less then a 3 dB change. Close to 0.6dB
Are you trying to change subject ?