Looking at having a custom power amp built

[Icarium]

Looking at push pull design versus a DHT design. I was told that DHT will not be able to result in as powerful an amp as push pull. Also what sound differences will I hear between a sick implemented DHT versus a push pull?

[Icarium]

Er I meant Set versus Push Pull. Also what other topologies are there?

[NotoriousBIG_PJ]

P-P is cheaper to implement. But if money isn't a problem... ^^

Biggie.

[Icarium]

Well I do have a decent budget but I think I'd like to keep it under 10k.

Can you elaborate on the various topologies and the pluses and minuses. And if you can.. which components are the key ones to maximize (I would guess its transformers all the cases).

Also important to me... what are the benefits of inefficient speakers versus efficient ones. I want this amp to scale with any sort of speakers I throw at it... so I am thinking about getting it to be pretty powerful (Potentially 500 watts per channel). Is that stupid? I am really into soundstage/clarity/details/midrange/bass tied with highs. I tend toward a clinical sound rather than a musical sound but nice tone and body is certainly appreciated as long as I get my soundstage and my details. Do efficient or inefficient speakers fit me better? Or does it not work that way... inefficiency/efficiency really has no affect on sound and its really up to the individual models of each type.

[Dusty Chalk]

Or does it not work that way... inefficiency/efficiency really has no affect on sound and its really up to the individual models of each type.

It's not so much that it doesn't matter, as the engineering is much more important than the resultant efficiency.

I would answer your other questions, but the first page I ran across when I googled SET vs. push-pull didn't jive with my understanding, so I'm just going to shut up. Try audiokarma.org, sh.tv or one of them other audio forums.

[Icarium]

I'm secretly hoping Kevin Gilmore/Aerius or some other figure that really knows this shit will elaborate.

Hrm okay good to know about the efficiency thing. Do you think I'd be stupid to get my custom power amp made hella powerful versus more fitting to my current and near-future needs?

I guess it will be potentially hell on the electric bill but... shrug.

[spritzer]

Using more then one output device will always give you some non-linear artifacts as they can't be perfectly matched. This has nothing to do with distortion as SET's have that in spades but it is second harmonic and we like that. SET's are also simpler as there is no need for a phase splitter so you can spend more money better parts but p-p will give you more power. You can have a 50w SET with the right tubes but that will cost a lot of money.

Spend the money on power and output transformers and what ever is used to couple the amp, either caps or transformers. You can also go vintage and discard electrolytic's completely in the PSU and use really big paper-in-oil's instead.

[boomana]

Just curious why you want to go custom. Is there something that you're looking for that isn't available right now? I think custom's great, but I also question if the one-of-a-kind plan might reduce what you can get for your money, but then again, if you get the right builder, you might end up with something real special.

[Dusty Chalk]

EDIT: Damnit, boomana, you beat me to it.

Do you think I'd be stupid to get my custom power amp made hella powerful versus more fitting to my current and near-future needs?

I do think that "hella powerful" is not necessarily a good match with all speakers. But based on your description of what you say you like, and based on my understanding of things, I'd say go hella powerful. I like hella powerful, myself (got a Musical Fidelity A308, myself). I would also add "monoblocks" to your thinking, especially if you're into soundstage/separation. (Both my MF and my Manley Stingray are "dual monoblock" designs.)

What I don't understand is why you're going custom. There are some mighty fine amps out there that will suit your needs (I think), well within the <US$10K mark.

I'm not saying "don't", I'm just trying to understand better.

Oh, and ... tubes? SS? Digital?

[Icarium]

Oh yeah I forgot to say these are definitely going monoblocks.

Yeah I wanted to get something with bizarre/ridiculous tubes. The opening talks with the people I might be having build my amp are talking about these Eimac tubes that in a push pull design can do like 500+ watts per channel.

[spritzer]

Go custom all the way you can get a lot of parts for just the dealer fees on a normal amp. You should choose the amp to match the speakers you are going to use so once you settler on what you want you can find the amp to match. More power is often the wrong way to go as a 20w tube amo will crush a 200w SS amp when faced with the insane load of an electrostatic loudspeaker and it will sound much better.

[Icarium]

Well I'm getting Green Mountain Audio Europa monitors to start. They are pretty efficient. We were powering them with a 25 year old 500 wpc Onkyo amp with matching preamp and it was drawing like a watt at the volume we were listening at. Though we didnt look closely at fluctuations...

[Icarium]

Basically I simply don't have the cash to go really full bore with the speakers I would want plus I haven't heard enough/read enough to know what i do want. I do like the 10k upper tier Green Mountain Audio speakers but again I haven't heard a lot. I've also had the Omega Super Hemps recommended to me by several parties. Plus I am not even really sure the space I have justifies really badass speakers. But I will have the space eventually and the desire to upgrade.

[deepak]

If you did eventually get a larger room and found out you liked efficient speakers (from what I've read from reputable places most of these people feel that music is conveyed best by SET amps) they probably wouldn't pair well with super powerful amps. Just IMO but it's ass backwards to choose the amps before the speakers.

[tkam]

Honestly I would not put any serious money into an amp until you settle on speakers.

[NotoriousBIG_PJ]

Go out and audition speaker setups

Biggie.

[aerius]

Basically I simply don't have the cash to go really full bore with the speakers I would want plus I haven't heard enough/read enough to know what i do want. I do like the 10k upper tier Green Mountain Audio speakers but again I haven't heard a lot. I've also had the Omega Super Hemps recommended to me by several parties. Plus I am not even really sure the space I have justifies really badass speakers. But I will have the space eventually and the desire to upgrade.

In this case I'd say the best thing you can do is spend the next few months to a year listening to as many speaker setups as you possibly can. Audition a bit of everything, electrostatics, horns, ribbons, single driver speakers, speakers with 10 drivers per side, high efficiency, low efficiency and everything in between. Find out what you like and don't like, and try to learn the whys behind it. After you've heard a bunch of stuff you'll start seeing which direction you want to go in and what's important to you, then you can make a short list of speakers and make your purchase after a further round of auditions. Then you can worry about the amps.

[Icarium]

Meh who am I kidding. You guys are right there's no way I'll get an amp that will work with whatever components I buy for the rest of my life esp. speakers. I am definitely getting the green mountain audio monitors. I think after talking/hearing from a lot of people I will be more into efficient speakers. So maybe 500 wpc is vastly overkill.

Still I haven't exactly been converted to speakers yet. I am getting some just because it makes sense in my living room and I'm going monoblocks since monoblocks are exciting to me.

[aerius]

Do more listening. It never hurts to have more knowledge & experience. That way you have a much better chance of knowing your choice is indeed the best one.

[deepak]

You should hear a pair of Avantgardes (in a good room)

[Dusty Chalk]

I realize this is a moot point, but I think this still needs to be pointed out:

I'm confused -- you're thinking about spending 10K on amps, but you can't afford 10K speakers? You should probably rethink your budget distribution.

[deepak]

That won't satisfy the amp fetishists Dusty.

[Icarium]

No I can afford 10-20k on speakers but I'm not sure how my space is accoustically yet. I am moving in Dec. 15. I'm going to feel it out with lower end speakers at first and then scale up a few notches and then move the monitors into my bedroom.

I realize that speakers are the most important part of the equation but they are also dependent on things more than the size of my budget.. i.e. my room and what it takes to work with whatever speakers plus I haven't heard all that many speakers. I realize that you can probably match speakers and amps pretty closely but I sort of question how many amps people actually hear with their speakers before choosing one that has optimal synergy. Like maybe I can find a particular amp that will work with a particular speaker and maximize the cost/synergy ratio... or I am thinking I can get a solidly designed/built amp from a maker I have experience with and though it may not be the single best matched amp... it will work out pretty well with whatever i get. Then the only question for me is how many watts i want it to push.

And yeah I have a bit of an amp fetish.

[Dusty Chalk]

Nothing wrong with that.

And yeah, feeling out your room(s) acoustically is a good idea as well.

I also agree with the advice of not being in any kind of rush, and auditioning as many speakers and as many different kinds of speakers as possible. That's always good advice.

[Icarium]

Kind of thinking about Electrostatic speakers now... my maker says that's what he personally goes for.