[amb]

I agree that when choosing the gain, you should have only as much as needed, and just a little more for extra adjustability (e.g., recordings that have lower than average level).

However, sometimes in "amp shootout" situations, the amp with the higher gain wins, because the uninitiated might associate a smaller amount of volume knob turn to achieve loud levels as "having more power".

The same situation exists in cars. Many cars are designed to "lurch off the line" with a small amount of accelerator pedal movement, because it gives people the impression of "power" during test drives. The reality is that there isn't much more as you press down the accelerator further.

I suspect that some of this might be influencing the outcome as a β22 with moderate gain is pitched against a speaker amp (which usually has a gain of 20 or more) driving the K1000.

 

[SoapSeller]

Quote:

Originally Posted by n_maher /img/forum/go_quote.gif Ack, missed that the first time somehow. All I can say is that you must listen a lot louder than I do.

Hmm, the 75% mentioned was with the K1000.
I'm listening in volume lower then anyone I've met up to this day

amb, there was no directed comparison of amps.
But-- on one hand, KT88 is a long time owner of those and heard them with a lot of amps.
on the other hand, he didn't heard any other part of my rig before.

We will be able to make some more comparisons in this weekend, and will report back.

 

[nnotis]

Does anyone else have something to add on this matter? I'm considering getting a β22 to drive both the K1000s and some extremely efficient speakers. But some of the posts I've read give me the impression that it may not perform too well with the K1000s, even though it provides ample power. Thanks!

 

[TimmyMac]

It will perform great. Build one with plenty of gain.

 

[starcat]

Hi guys,

anyone who has build the ß22 and has listened to other high-end amps like WooAudio or Blue Hawaii SE, can you try a comparisson? Thinking about building a 4 beta22 with 4 sigmas amp for my K701 which I am going to recable for balanced. On the other hand I am pretty darn shure I will get a Stax O2 some day soon with either the Woo GES or something similar, so I was thinking if I should pull out $1k for the beta22 for my K701 or just save this expense and upgrade to the O2 and leave the K701 unbalanced for my Shanling PH100 class-A headamp. Any thoughts highly appreciated!

PS: All my sources like DACs, CD players, etc are balanced.

 

[Atchoum]

Quote:

Originally Posted by ericj /img/forum/go_quote.gif I'm curious, where are people getting this wacky idea that less gain is better?

Isn't simply because less gain = less amplified/multipliated noise coming from the source.

 

[amb]

Quote:

Originally Posted by Atchoum /img/forum/go_quote.gif Isn't simply because less gain = less amplified/multipliated noise coming from the source.

Not only that, but also less amplified noise coming from itself. The amp's own input stage noise is amplified along with the signal.

Ideally you should have enough gain for your application to reach intended maximum output, plus a bit more for adjustability/headroom (such as for a recording with weak average levels), but no more.

 

[ericj]

Quote:

Originally Posted by amb /img/forum/go_quote.gif Not only that, but also less amplified noise coming from itself. The amp's own input stage noise is amplified along with the signal. Ideally you should have enough gain for your application to reach intended maximum output, plus a bit more for adjustability/headroom (such as for a recording with weak average levels), but no more.

I'm mostly just confused by people who aim below that target.

 

[cotdt]

4 Beta22's and 4 Sigma22's, or alternatively an unregulated power supply. I think the unregulated PSU is really worth checking out, since it's much cheaper than 4 Sigma22's and the Beta22 has a very high PSRR. Clean power should not be needed, so long as the power supply is big enough to avoid big voltage drops.

2 Sigma22s should be enough if you give them big heatsinks. The Balanced Beta22 really sings with speakers, and you don't need efficient ones. It's a really high end design and should hold its own against any power amp. Balanced Beta22 has plenty of power. Give each amp board big heatsinks. At least 8x gain on each amp board, which translates to 16x gain in balanced mode, not that different from speaker amps.

 

[lynxkcg]

It's late and I'm probably not thinking clearly, but would wiring up a 50k stepped attuator AND a 10k in series be worth trying? Kinda like having a separate rough volume and fine volume knob?

 

[cotdt]

Quote:

Originally Posted by lynxkcg /img/forum/go_quote.gif It's late and I'm probably not thinking clearly, but would wiring up a 50k stepped attuator AND a 10k in series be worth trying? Kinda like having a separate rough volume and fine volume knob?

you can add a "gain switch" which technically doesn't change the gain but "low gain" would be like -20dB attentuation.

 

[n_maher]

Quote:

Originally Posted by cotdt /img/forum/go_quote.gif 4 Beta22's and 4 Sigma22's, or alternatively an unregulated power supply. I think the unregulated PSU is really worth checking out, since it's much cheaper than 4 Sigma22's and the Beta22 has a very high PSRR. Clean power should not be needed, so long as the power supply is big enough to avoid big voltage drops.

We are talking about driving K1000's here and not big speakers right? If so, a 2-channel, single power supply design is more than sufficient to drive them well in my experience. No need for the insanity you're preaching.

 

[swt61]

Quote:

Originally Posted by n_maher /img/forum/go_quote.gif We are talking about driving K1000's here and not big speakers right? If so, a 2-channel, single power supply design is more than sufficient to drive them well in my experience. No need for the insanity you're preaching.

X2

I drive my Omega Grande Six speakers effortlessly with two sigma22 power supplies.

 

[cotdt]

Quote:

Originally Posted by n_maher /img/forum/go_quote.gif We are talking about driving K1000's here and not big speakers right? If so, a 2-channel, single power supply design is more than sufficient to drive them well in my experience. No need for the insanity you're preaching.

I thought the thread title meant a B22 configuration for both K1000s and speakers? I agree that contrary to popular belief, K1000s are relatively easy to drive so long as you have enough gain.

 

[amb]

Quote:

Originally Posted by cotdt /img/forum/go_quote.gif I agree that contrary to popular belief, K1000s are relatively easy to drive so long as you have enough gain.

Yes, and a copious amount of output voltage swing headroom, because the K1000 is so inefficient. That is why many people use speaker amps to drive them, not for the sheer power (which the K1000 won't use anyway, it has 120 ohms impedance, not 8 ohms), but for the gain and voltage swing.