the cheapest route to high end audio... Naim clone? Blameless? digital?

[nannoo]

Hi guys,

Like a lot of people I thought I knew a lot about audio engineering before I started this hobby, months later after building my own speakers I've really learnt to appreciate how much work goes into the design process, and how much knowledge is needed/used in design (and is available on this forum).

As I student I can't afford much, at the moment I have a second hand denon AV amp (AVC A10SE) which was very cheap on ebay and does relativly well for what it is.

obviously one day (sooner rather than later if possible) I'd like to have a more high-end amplifier.

In the loudspeaker forums people recommend building an established design, are there established DIY amplifier designs that can be recommended?

What about the naim clone DIY module on ebay?
Or any of the digital amplifiers?
Am i right thinking that the blamelss modules are pretty much 'as good as it gets' for honest amplification?

I don't have a budget for this yet, but it'll most likely be in the £400 range for the completed amp, though I'd be happy to used a 'make do' PSU and build a much better one in the future if it would offer any advantages.

Also, if people could let me know what they think I should be 'expecting' from this kind of power amp compared to commercially available models.

 

[ostripper]

Am i right thinking that the blameless modules are pretty much 'as good as it gets' for honest amplification?

Pretty much the most cost effective. I'm pricing/stuffing a blameless (DIYA honey badger/blameless) for $30usd. With boards $100-pair.

If you really want cheap , Ebay a used/broken pro amp with trafo (transformer)
and large heatsinks - modify , and $200-$250 USD is all you need for 150-180 w/ch.

OS

 

[pilli]

I have built a DisPre + SymAsym for certainly less than the amount you target.
The JLH should also be well within range.
(Well, assuming you already have some build and test equipment...
soldering, tinkering, multimeter, oscilloscope, ...)

You should also really look at FIRST WATT
and the designs by Nelson Pass, they come "in any size you want".

Search for those names on this forum.
Of course there's many more projects...


(Mine is just a very humble and partial suggestion; for example, I have never done anything with "digital" or chip amps... like, not even listened to one...)


-

 

[PMI]

Lazy Cat is starting another Group buy for his VSSA module kits, 38 euro per pair (plus a few euro for capacitors that you have to buy yourself). Most people are blown away by the sound from such a simple circuit.

http://www.diyaudio.com/forums/vend...lateral-mosfet-amplifier-204.html#post3578509

There is also Shaan's version of the same concept, which you can build completely from the ground up, using conventional through-hole parts, here:

PeeCeeBee

I think my total parts cost in the US was about $50~55 for two boards.

Another option is Bonsai's nx-Amp, which is complete including power supply, protection circuit, etc., here:

http://www.diyaudio.com/forums/solid-state/236522-sx-amp-nx-amp-15.html#post3575480

There is probably no one single "best" power amp to build on a budget. The trick is to find one you a) like, and b) can build with your resources.

Most of the cost of building your own power amp will be in the chassis, and then in the transformer and power supply. About 75%, I would say.

It pays to shop around for used toroidal transformers, you can usually find them for half the retail cost, either used, or from someone who is clearing out their stock of parts.

Pic of boards I built from Shaan's thread for around $50, power supply is MrEvil's Capacitance Multiplier (about $30-40 depending on the cost of the large capacitors), heatsinks from HeatsinkUSA (about $13 each):

 

[jcx]

build amps if you're a electronics hobbyist - not for "quality audio"

Geddes doesn't seem to think "transparent" audio electronics is hard to do, and good enough electronics can be had very cheaply

his waveguide speakers, selling for $3k each, were demoed with < 3% of a pair's price in his mass market consumer amp

Originally Posted by gedlee
You can believe it or not, but its true. I tested about five amps that I had and the Pioneer was the best.

People always take my statements out of context. Once one has good electronics - and clearly price and "personal perception" don't correlate with good - then the only thing that matters is the speaker and the room (source material being a given). I have never said that any piece of junk electronics is fine. Only that very inexpensive and readily available electronics place the electronics into the "insiginificant errors" category.

I know that this is not a popular position and it's not one that I have always held, but I have studied this problem intensely and this is my conclusion. It is, by the way, the same one as held by Flyod Toole and Lauri Fincham and a whole host of other well know audio researchers. It's amp designers and marketers who seem to hold contrary beliefs

Originally Posted by gedlee
No hardly - I don't "favor it", but I was severly chastized for using it at RMAF when, in fact, no one really knew if it was any good or not. It works just fine as my measurements show. I would not use this amp for many applications, but it suited my point at the time, which was that loudspeakers account for 99% (well you could argue 98%, but you get my point) of the audio systems sound quality.

The amp is a Pioneer DSX-V912 - a receiver. The point is that it was on sale at Costco for $150.00. I bought several of them for home theater use. I used my test to measure the amps and they were quite good actually. Especially for chip amps. I was measuring a lot of chip amps (a survey of capability) and most were pretty bad. As a chip amp this unit deffinately stands out. It compared quite favorably to a very well engineered discrete amp that I also use.

I also tested several other receivers and they were almost universally bad.

Originally Posted by gedlee
Crossover distortion is a particularly insideous form of nonlinearity because it happens at all signal levels and there is no comparable mechanism in a loudspeaker to mask it. The question was asked if I have a way of identifying crossover distortion in an amplifier.

Yes, I do.

You see the situation with crossover distortion is that the % distortion increases with falling signal level. This is exactly why it is so audible since this is directly opposite to our hearing.

One could therefor ***** crossover distortion by looking at THD as the signal level goes lower, which is a typical measurement. The problem is that virtually all of these THD versus level measurements are THD + noise. When this is the case, the rise in THD at lower signal levels is actually the noise and NOT the distortion, but it is impossible to tell which is which. SO this test actually masks the real problem. One would have to track the individual harmonics of the waveform, but then the noise floor is still an issue.

Hence the measurement problem is one of noise floor and how to measure distortion products down below this floor.

This is done by averaging. But normal averaging can only lower the noise floor so much - down to the noise power. But if I have a signal and I average this signal sychronously then I can raise the net signal to noise level. This too is common. But if the signal does not exactly fit the time base then I need to window it and the resultant spectral leakage makes this sychronous averaging less effective.

I use a signal that exactly fits into the time base of the A/D taking the data. This means that I don't have to use a window and I can sychronously average a signal to noise ratio that is about 20 dB better than a simpler test could achieve. This means for example that the input signal needs to be something like 976 Hz, not 1000 Hz, which doesn't exactly fit the window.

I actually had to generate the input wav file in FORTRAN using quad precision, special random number generators and rounding techniques, because the test signals needed to have a 120 dB dynamic range - very difficult with 16 bits.

I use a signal that starts out low and goes up in level. I plot out the results as the signal drops into the noise floor. This test shows vast differences in amps that measure identical with standard tests.

It also shows that my Pioneer amp - you know the "really crappy" one that I get crticized for using at RMAF - is an extremely good amplifier. As good as the best that I have tested with this technique.

basically if you're serious about improving audio reproduction with finite time and knowledge - don't build amps - just buy cheap adequate ones, spend the time and dollars on speakers and room

 

[PMI]

Geddes doesn't seem to think "transparent" audio electronics is hard to do, and good enough electronics can be had very cheaply

A lot of people are very dismissive of the influence of electronics on sound, usually, because it is something they either do not understand, or, because they understand it very well, and are selling something else to those who do not.

his waveguide speakers, selling for $3k each, were demoed with < 3% of a pair's price in his mass market consumer amp

That only proves that if you control the test conditions, you can control the outcome of the test.

By any chance, he wasn't selling those speakers that can make a Pioneer chip amp sound like a million bucks, and only for $3K each, was he? What a fortuitous coincidence!

 

[jaycee]

The main costs in building an amp are the mechanicals - case, heatsink, transformer. Reusing an older broken amp is good for reducing this cost

There is a lot of snobbish attitude, but a well implemented LM3886 based chip amp can give good performance for the simplicity and cost.

 

[PMI]

The main costs in building an amp are the mechanicals - case, heatsink, transformer. Reusing an older broken amp is good for reducing this cost

There is a lot of snobbish attitude, but a well implemented LM3886 based chip amp can give good performance for the simplicity and cost.

I would agree with that, there is a lot less that can go wrong with chip amps in construction, and reusing/recycling anything gets a from me any day. There are lots of old chassis, sadly with perfectly good transformers that land in the trash every day. One set of VSSA boards I built from Shaan's thread is working quite happily in an old case like that.

 

[jcx]

I do EE, like circuit design, earned a living at it - but can't see the big deal with stating priorities that are supported by the evidence

Speakers, Rooms matter, differ the most in reproducing recorded sound


yes Dr Geddes is selling the waveguides, speakers, as kits and up to finished products direct for ridiculous low value for his time

and he has published the waveguide design and distortion audibility listening tests in peer reviewed journal articles


but I don't get your logic - he's not selling the cheap amp, he clearly states that many cheap amps fail his distortion audibilty measurement criteria


in many threads here he has discussed his experience of waveguide building, driver selection, measurements with soundcards, amp testing - disclosing materials, tools, part # - very much in the spirit of supporting DIY


Carver however was at the time selling a "cheap amp" by audiophile standards when he issued the null test challenge to Stereophile's "Golden Ear" reviewers:

http://www.diyaudio.com/forums/solid-state/12752-blind-listening-tests-amplifiers-55.html#post152392

For those who might be interested, I dug up the Carver Challenge article in Stereophile. The brief background is Bob Carver (the man behind Phase Linear, Carver and now Sunfire) made it known to the press he would put his inexpensive amplifiers up against ANY amplifier in a blind test if he had a few days to adjust the transfer function of his amp to match the challenger's amp. Stereophile took him up on the challenge and here are some quotes from the article written by J. Gordon Holt:

"We knew that Carver couldn't possibly pull this off, at least not to the point where none of us would be able to distinguish between his modified 1.0 and our reference amp. After all, some of the most highly trained audio ears in the world would be listening for the differences."

"...the reference unit is a high-powered, very expensive stereo unit with a strong and unique sonic "personality" and a penchant for being very finicky about the loudspeakers it works with. It was, we were gleefully confident, likely to be very dissimilar in sound from Carver's own designs."

"Not surprisingly, the reference amplifier sounded very different [from the Carver] and, in our opinion (shared, in most respects, by Bob), much better."

"Bob didn't have to concern himself about quality capacitors, minimal internal wiring, gold connectors, or any of those things; all he needed to do was duplicate, at the output of his amplifier, the sum of their effects at the output of the reference amp. Once he had obtained the necessarily deep null between those amplifiers, it was his belief that ears were not going to pick up on what was left."

"After the second day of listening to his final design, we threw in the towel and conceded Bob the bout."

"We had thrown some of the most revealing tests that we know of at both amps, and they came through identically. Even on the subliminal level--the level at which you gradually get the feeling that one amplifier is more "comfortable" than another--we failed to sense a difference between the two amps."

"We wanted Bob to fail. We wanted to hear a difference. Among other things, it would have reassured us that our ears really are among the best in the business." (italics emphasis in original article)

"According to the rules of the game, Bob had won."

"The implications of all this are disquieting, to say the least. If, after only four days of work, it is possible for someone--design genius or not--to make a $700 amplifier sound exactly like a state-of-the-art amplifier costing many times as much, what does that say for the cost-effectiveness of the latter?"

The amplifier used was a Carver M1.0 selling for $699. Bob used null difference testing to tweak the M1.0 until he obtained a deep null with the (unnamed) Stereophile tube reference amp. They did not reveal the reference amp because they felt it would be unfair to that manufacture who might ask: "why us?".

It was later revealed the most significant modification Bob made was to simply put some series resistance into the output of the M1.0 to better approximate the much higher output impedance of the tube amp. The other tweaks were supposedly limited to a small R-C network in the feedback loop.

It should be noted that J. Gorden Holt was the Editor-At-Large and Chief Tester at that time. Larry Archibald, the Publisher, and John Atkinson, the International Editor and a frequent reviewer, also participated in the listening sessions.

The challenge showed two things IMHO:

1 - It validates null difference testing with "some of the most highly trained ears in the world". Bob simply nulled his amp to the reference and JGH, JA and LA at Stereophile could not tell them apart.

2 - It shows that you don't need expensive components or exotic techniques to make a very modest amplifier with mainstream parts sound like a much more esoteric amp.

Bob literally bought the components used to modify the stock M1.0 at Radio Shack and worked out of his hotel room in Sante Fe (home of Stereophile). He made a 20 pound (9kg) mass production solid state power amp full of cheap parts (with a rail switching class-G power supply no less) sound so close to a very expensive heavy monster tube design that some of the mightiest GoldenEars couldn't tell them apart.

Considering that Stereophile is mainly filled with ads from high-end vendors hurt by the outcome of the challenge (versus just one advertiser--Carver helped by it), and that everything would point to the editors not wanting to admit a $700 amp can sound the same as a five figure one, I have to assume they wrote an accurate article and were not paying Bob any special favors.

 

[mcd99]

The main costs in building an amp are the mechanicals - case, heatsink, transformer. Reusing an older broken amp is good for reducing this cost

Agree, I have two matching broken amps with what look like 750VA transformers in them. + two heat sinks + obviously case work.

All in all a great way to save money. 50 nicker a piece.

 

[PMI]

@jcx: The point about distortion audibility is well made, I pretty much agree with that, and it is good to be reminded that crossover distortion is more audible at low listening levels, etc.

My point was not very well made.

It is true that the average speakers (and room) contribute more distortion on top of a typical consumer power amp or receiver. However, one should not use that as an argument to start improving a sound system from the speakers backwards. That is a salesman's argument, not and engineer's. Like buying a car with a nice interior and a poor engine.

You need to start at the source, because if the source of the signal is poor, or if the sound is distorted in the amplification process, you will not even be able to choose speakers that suit your personal preferences.

In any case, to the best of my knowledge, you can't solve the speaker/room issue for under £400. You can however build any one of a dozen power amplifiers in this forum for much less than that, and outperform a typical consumer system (at low-moderate single-room listening levels).

aside, and off topic: The Bob Carver challenge is an excellent example of what I stated above, if you control the test, you control the outcome. That does not make his amplifier bad by any means, not my point. He was one of the best engineers of the time who was also an excellent salesman. Go to the Carver web site, or read some of the descriptions of how the "tests" were done... as an engineer, and a EE, not as an audiophile...

Peace

 

[Studio Au]

Ive got a old rotel RMB 1048, connected to a miniDSP to build some 4way active speakers.

I also want to build a single ended valve amp to power some Mark Audio small full range speakers.

What speakers are you powering, will you use a no crossover, a passive one or a active digital one?

I have been watching these Elekit (active on this forum i believe) Under £200 DIY

ELEKIT TU-870R 6BM8 Tube Power AMP (Kit) | eBay

 

[nannoo]

I'm looking just at a stereo power amp at the moment, possibly later I will add a decent quality dac/pre, then if there is benefit I will add a dedicated seperate PSU.

I will always be powering a speakers with passive crossovers, though they may be augmented by a DIY bass bin depending on if anyone replies to my other thread

I'm not a fan of bi-amping, digital active crossovers though i DEFINATELY like, especially the kit on this forum somwhere.

From the responses, given that a lot of the cost will be psu/case/protection circuits and other sundries, is it logical to have a selection of power amplifier modules within the case for comparison? i.e. naim clone, blameless, and a decent digital amp?

 

[Studio Au]

Ive got the miniDSP 2x8, only just up an running. Purchased it with all the bits, DigiFP and Vol FP along with a Mic.

This allows digital and analogue in, with a physical volume and source switch control as well as operation through (almost) any remote control. And active crossover. And with the mic and REW you can do room optimisation.

Not many products can get you this at that price. You could buy some good second hand amps for the change or build some simple chip amp ones. Just one option. Havent had mine long enough to get it fully working, I know the DAC's onboard aren't the best, but still seems like a great product.

 

[jcx]

Originally Posted by PMI:
That only proves that if you control the test conditions, you can control the outcome of the test

clearly we have a completely different world views, understanding of the meaning of controls in listening tests

I refer to controls as in experimental controls
for audio listening comparison 0.1 dB level matching, frequency response matching over audio frequencies is required
any sensory perceptual experiment, relying on reporting of conscious sense impressions, has to be Blinded - preferably Double Blind

lossy audio CODEC development has tested these principles/limits, the statistical resolving power of listening tests very thoroughly across many thousands of subjects – see Hydrogenaudio, MP3' Tech - Technical papers

The Bob Carver challenge is an excellent example of what I stated above, if you control the test, you control the outcome...

I really don't see how it can be claimed Carver somehow controlled the Sterophile reviewers - they were in their listening room, using their choice of "good" amp, their speakers, their source, music selection, listening for any difference their experience as professional audio reviewers could find

the only “controls” I see claimed were the level matching and Blinding after Bob nulled the output terminal electrical response between the amps with a small handful of parts added to his SS amp to tweak its response to match Stereophile's selected tube driving their selected speaker

 

[a.wayne]

Hi guys,

Like a lot of people I thought I knew a lot about audio engineering before I started this hobby, months later after building my own speakers I've really learnt to appreciate how much work goes into the design process, and how much knowledge is needed/used in design (and is available on this forum).

As I student I can't afford much, at the moment I have a second hand denon AV amp (AVC A10SE) which was very cheap on ebay and does relativly well for what it is.

obviously one day (sooner rather than later if possible) I'd like to have a more high-end amplifier.

In the loudspeaker forums people recommend building an established design, are there established DIY amplifier designs that can be recommended?

What about the naim clone DIY module on ebay?
Or any of the digital amplifiers?
Am i right thinking that the blamelss modules are pretty much 'as good as it gets' for honest amplification?

I don't have a budget for this yet, but it'll most likely be in the £400 range for the completed amp, though I'd be happy to used a 'make do' PSU and build a much better one in the future if it would offer any advantages.

Also, if people could let me know what they think I should be 'expecting' from this kind of power amp compared to commercially available models.

Cheapest way is to buy used , DIY will cost more with uncertainties with performance , DIY is sbout the journey, unless you know enuff to build a first class amp , then Its cheaper to DIY ...

 

[a.wayne]

Geddes doesn't seem to think "transparent" audio electronics is hard to do, and good enough electronics can be had very cheaply

his waveguide speakers, selling for $3k each, were demoed with < 3% of a pair's price in his mass market consumer amp








basically if you're serious about improving audio reproduction with finite time and knowledge - don't build amps - just buy cheap adequate ones, spend the time and dollars on speakers and room

Good speakers are a must and so is the electronics, Low resolution speakers will mask details not so with a good pr of speakers, differences abound....

 

[Conrad Hoffman]

Cheapest way is to buy used , DIY will cost more with uncertainties with performance , DIY is about the journey, unless you know enuff to build a first class amp , then Its cheaper to DIY ...

+1
You do DIY because you enjoy the DIY journey. It is not cost effective if all you want is an amp. You have to establish your real priorities. If you can fix amps, the fastest cheap path to a better amp is to buy a broken one and fix it. Next step over is to buy a broken one for the chassis and PS parts, then put new circuitry in. That can be a published design or one of your own creation. IMO the latter is risky until you've had some experience, but you have to start somewhere. You also have the advantage of the books by Doug Self and Bob Cordell, plus the 'net, that we never had back in the bad old days. If you want the ultimate challenge, build a high end amp with zero outlay, using just what you can find at the curb or at the dump. Laugh if you want, but it's entirely possible if you're clever.

 

[nannoo]

the problem with buying second hand to repair is that a lot of the high end amps go for silly high money even when broken on ebay... I'm guessing there's a lot of people out there with more experience than me thinking the same thing. That said I picked up a certain AV amp that used to retail at £2000 for £28 and repaired it no problem...

Same with second hand gear, naim amplifiers (which I'm a massive fan of) seem to hold there price very well and stay well above the £400 mark.

I was hoping that even buying a turn key set up of pre-assembled models, such as the blameless amplifiers, would offer me better value for money. Is this not the case?

 

[PMI]

I was hoping that even buying a turn key set up of pre-assembled models, such as the blameless amplifiers, would offer me better value for money. Is this not the case?

Personally, I believe that is true, especially as it relates to the guts of the amplifier. Total cost depends on how much you spend on a chassis and other small parts. It can add up quickly.

Repairing old gear is almost an art, and it can take more expensive parts, tools, and instruments to do it right than to build new. The high prices reflect nostalgia, not necessarily quality of the sound.