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Tube amp with cheap transformers 'useless' ? - Page 4

post #46 of 106
Quote:
Originally Posted by estreeter View Post

Harsh, and I cant see that it was called for.

 

I set out to clarify the situation regarding transformers for you. It's shouldn't be necessary to spend $1500 to get a reasonable tube amp IMO. You won't get any better sound anyway than $100 spent building an O2. Guys who are selling these things disagree. Evidently the answer I gave wasn't what you wanted to hear. I'd no sooner have one of those things than a $20,000 crocodile skin handbag, but if it's what you want you'd better start saving.

 

w

post #47 of 106
Quote:
Originally Posted by wakibaki View Post

 

It's gross margin, nikongod.

 

I'm not ignoring economies of scale, I don't expect a small company to operate at 26% gross margin, I expect maybe 4~8 times that.

 

I've got a design of my own with a parts cost of ~$100 I've considered marketing. Even hand building them myself I'd feel uncomfortable charging much more than $200, in fact I'd hope to come in a bit below that. Wouldn't you?

 

 

Wikipedia:

Gross margin (also called gross profit margin or gross profit rate) is the difference between revenue and cost before accounting for certain other costs. Generally, it is calculated as the selling price of an item, less the cost of goods sold (production or acquisition costs, essentially).

 

Production cost... 

Neat. There is no way that a refrigerator company is making 26% on the cost of raw materials. 

 

For your amp:

If its anything but a hobby $200 wont be enough. 

If its a hobby thats a whole different story, but people do support their families on this business. 

Quote:
Originally Posted by wakibaki View Post

 

I set out to clarify the situation regarding transformers for you. It's shouldn't be necessary to spend $1500 to get a reasonable tube amp IMO. You won't get any better sound anyway than $100 spent building an O2. Guys who are selling these things disagree. Evidently the answer I gave wasn't what you wanted to hear. I'd no sooner have one of those things than a $20,000 crocodile skin handbag, but if it's what you want you'd better start saving.

 

w

 

Can you objectively define what criteria you used to say that the O2 "sounds better" than a hypothetical $1500 tube amp? 

The fact of the matter is that the 2 amps sound different. 

The O2 is the only "measurements first" amp worth building at this point (it can back its measurements, and after that its the cheapest) 

Subjectively.... There are so many reasons not to build the O2. That you don't like how it sounds is a good start. 

post #48 of 106

You said 'Did the refrigerator company include cost of MFR (man-hours, storage, and transport)' and I said it's gross margin.

 

The difference between COST and SELLING PRICE. COST including material, premises, personnel, transport, fuel etc. Production cost.

 

I never suggested it was materials cost.

 

Materials cost, however, in the case of a small company, is the majority of the cost. A small company has no chairman, board of directors, managers, HR department, corporate jet, health insurance etc. etc. etc., so markup on parts cost is roughly equivalent to gross markup. Oh, and of course, shareholders. Try to bear in mind that I am an engineer. Pi is roughly 3. Do I have to spell everything out? 

 

If I build one in an hour, I'd be paying myself $80 an hour leaving $20 for other costs. My amps are surface mount, I can probably build half-a-dozen (the size that fits my reflow oven) in an hour once I get organized.

 

Even if it takes 2 hours to build a tube amp, and it shouldn't take any more if the line is well organised, you could still disappear the cost of labour in the 100% markup on parts cost.

 

That's what I used to do. Design for manufacture.

 

You're damn right I can objectively define the criteria. Not only that, I can sum them up in one word. Transparency. Hi-fi is about high fidelity in my book. If you don't like it go read some other book. The O2 is transparent. You won't get a BETTER sound in those terms. You might get one you PREFER, but only because it's not transparent.

 

Is there anything else?

 

w


Edited by wakibaki - 8/15/12 at 9:34am
post #49 of 106

1000

post #50 of 106

Actually I don't think shareholders count as part of production cost.

 

I'd have been happy to let it go a while back. All I set out to say was that IMO $1500 is excessive for a tube headphone amp and that I believe a perfectly good one with entirely satisfactory transformers could be built and sold for half that or less. I mean, you can buy a 12W tube amp from China for less than $300 shipped.

 

Anyway, I'm done here.

 

w

post #51 of 106

I just couldn't resist it, I just found this in another thread, it precisely makes my point. Thanks, nikongod.

 

http://www.head-fi.org/t/553094/continued-sidetrack-discussion-from-tiniest-portable-amp-i-can-build-nikongod-microtransformer-based-impedance-step-down-box

 

 

 

Quote:
Originally Posted by jdkJake View Post

Transformer specs for those interested:

 

IMG_1871.JPG

 

 

Quote:
Originally Posted by nikongod View Post

glad you like it :)

 

As a point to (hopefully) save face, the transformer bandwidth is measured a rated power - these little guys are toooooo small to have a hope with 1W :p. At the tiny power levels used by headphones they have MUCH better bandwidth that advertized. I'l measure them again tomorrow. 

 

Quote:
Originally Posted by nikongod View Post

So I remeasured these just a second ago. 

 

All measurements taken on the "full" primary (blue to green) and with a 1vp-p input signal 

 

Little radio shack transformers
1vp-p input 32ohm 12.4ohm 8ohm
-1db high frequency 250Khz 55Khz 45Khz
-1db, low frequency 50hz 50hz 45hz

 

Its worth repeating, these are the -1db points (-10%) NOT -3db. 

NOTE: on 32r, the transformers DO reach 20hz just before the -3db point, but they are clearly saturating and looking ugly. With a smaller input signal (I tried at 200mvp-p) they reach 20hz clean, although still about 3db down.I didnt bother checking with the other 2 impedances.

 

About the only thing that goes below 60hz is organ music. IME most bass in pop music is in the high 50/low 60's. 

 

w

post #52 of 106
Quote:
Originally Posted by wakibaki View Post

...I've got a design of my own with a parts cost of ~$100 I've considered marketing. Even hand building them myself I'd feel uncomfortable charging much more than $200, in fact I'd hope to come in a bit below that. Wouldn't you?...

Quote:
Originally Posted by wakibaki View Post

...Materials cost, however, in the case of a small company, is the majority of the cost...

 

Like nikongod said, if you're going to build/sell as a hobby, and/or do it as a favor to the community--and you've got the time to donate to the cause, and you value your time at zero to fulfill your equation--then, yes, coming in below $200 should work just fine.

 

If you're going to do it with an intent to make a living (or even just to make a little money on the side), then try operating with your above-quoted assumptions, and let us know how that works out for you.

 

Now I guess I should check out the first post in this thread to see what this thread was supposed to be about.

post #53 of 106
Thread Starter 

For the sake of completion, I posed the question earlier in this thread re cheaper OTL designs - 

 

http://www.headfonia.com/lafigaro-339-my-fav-otl-amp/

 

The La Figaro 339 is available from Yuking09.com directly and costs $550 without shipping. A price that I think is “a steal” for such a great amp. I’m convinced that if this amp was built in the USA or Europe it would get a lot more praise (as it deserves) and a higher price tag.

post #54 of 106
Quote:
Originally Posted by jude View Post

 

Like nikongod said, if you're going to build/sell as a hobby, and/or do it as a favor to the community--and you've got the time to donate to the cause, and you value your time at zero to fulfill your equation--then, yes, coming in below $200 should work just fine.

 

If you're going to do it with an intent to make a living (or even just to make a little money on the side), then try operating with your above-quoted assumptions, and let us know how that works out for you.

 

Now I guess I should check out the first post in this thread to see what this thread was supposed to be about.

 

One of the things I'm pointing out, jude, is the O2 on sale from JDS labs @ $144 US, which I reckon to be ~ twice the parts cost. A lot has been made of the necessity for higher markups for companies to survive, but what I'm saying is that the JDS labs price simply demonstrates the proper operation of competition. The item can't be sold at a greater markup because it would be undercut by somebody else, who would see the opportunity to make a worthwhile profit. 

 

I don't deny that companies have costs other than parts costs, but IMO, once prices start to exceed 3 times the parts cost, purchasers should start to question whether they are getting value for money.

 

The point will be quite adequately proved if the O2 continues to be sold at its current price point. Care to take a bet on it? $100 says it will still be available under $150 from some supplier or other in a year's time.

post #55 of 106

The O2 has no bearing whatsoever on the costs of tube and/or transformer-based amps, period, end of story.

post #56 of 106

A bit more -

 

I apologize - I didn't want to post in this thread, because obviously, there was some ignorance in play about private business costs.  It may be more fundamental than that, though, and some of it may simply go to the differences between solid-state and tubes.

 

It seems to me that from the last couple of posts, the tube amp prices discussed earlier in this thread were thought to represent more than 2X the cost of producing it. That particular point was never even debated in the thread AFAIK (sale price = 2X cost). It was more of an absolute challenge as to how much something should cost, period. As with anything in audio, you will pay 90% more for the last 10% in performance. That makes pricing a product a highly variable thing. You could try to reference the RatShack transformers that jdkjake and nikongod were discussing, but that was in the context of a DIY discovery. As in, "Hey, these things look half decent. Maybe they're worth experimenting with in certain situations and that might be fun."smily_headphones1.gif

 

On the other hand, if you're trying to compete with amps at a level of "beyond reproach" (a phrase used early on in this thread), then you might end up paying $500 for some outstanding ElectraPrint transformers that have no dB drop whatsoever at 50Hz. Add in a tube pair that might run $100 and a case that could easily approach 30-50% of the total cost, and you hit $1000 in basic costs pretty damn quickly. Assuming your minimum of 2X cost to make a profit (a fair ratio for a small, one-man shop), then you can hit $1500 retail price without hardly trying - more like $2000 or higher, if even more "boutique" parts were used for a "beyond reproach" quality.

 

All of that assumes that someone recognizes the advantages/special features of tubes, the O2 notwithstanding ...  Conversely, I think AMB has mentioned many times that the B22 - if built commercially - could easily approach $5000.  Examples of electrostatic amps costing that much and more can easily be found.  I think Jude summarized it pretty well - there's a price for building one yourself, where you don't have to count custom casework, packaging, shipping prices, most-importantly - the investment float - but it's extremely unfair to challenge someone that you could offer to sell it cheaper because you think you might be able to build it cheaper (by forgetting to count all those extra miscellaneous costs).

 

Try making 100 complete kits of whatever amplifier/DAC you choose - including PCB's and a custom manufactured case.  Then count the parts packaging, the instructional documentation, your time, purchasing parts in high volume, custom manufacturing orders, etc. and as mentioned above - the financial float required to assume the risk for however long it will take you to sell enough to just re-stock ... and see how that cost works out.


Edited by tomb - 9/2/12 at 8:41pm
post #57 of 106
Thread Starter 
Quote:
Originally Posted by tomb View Post

The O2 has no bearing whatsoever on the costs of tube and/or transformer-based amps, period, end of story.

 

Agreed. Its also a product where the manufacturers paid zero dollars for the R&D and need to do minimal assembly to arrive at a finished product. How many people have a business assembling Bottlehead kits and selling them for double the kit price ?  Bottlehead even give you the option of including their badge with the kit, leaving the field wide open for your own badge - couldn't be simpler, yet I dont see anyone offering this service. Perhaps the labour involved doesn't add up to a viable business proposition ?   

post #58 of 106

And from my own experience, without a huge outlay in marketing- advertising, going to shows, giving product away for reviews, etc. you never sell enough to pay back your original investment. I went into this with an altruistic and somewhat naive goal of building a high-quality product that normal people could afford, but it turns out that normal people don't spend $3K on a 100WPC tube amp no matter how good it is for the price. It is a small market within a specialty market. So it's out there but if nobody knows it exists then nothing sells.. and if you spend the big money for marketing then you either lose your ass or have to raise prices to pay for it.

post #59 of 106

Just to throw this out there: http://www.bottlehead.com/smf/index.php/topic,3277.0.html

Bottlehead now charges their shop rate of $65/hour to build their kits. That adds up fast.

post #60 of 106
Quote:
Originally Posted by elliottstudio View Post

a high-quality product ... $3K ... 100WPC

 

 

100WPC is a LOT for a tube amp. It probably has 4 tubes per channel in each output stage alone. He's still only quoting $3k
 
The rest of this is not aimed at elliottstudio in isolation.
 
Do you deny that there is a radical improvement in OP transformer performance when used at power levels significantly below their maximum rated power? Did you even bother to look at the manufacturers figures in post #51 and compare them with the figures produced by nikongod at reduced power? This is not a ''DIY discovery', this is a well known fact and simply a consequence of physics.
 
These are improvements obtained in a 1W transformer with a 300Hz -3db rolloff. The performance improves to -1dB at 50Hz. Consider instead the likely performance of a 10W transformer with a 50Hz etc. etc.
 
Do you deny that the very large majority of headphones work with milliwatt power levels?
 
The title of the thread is 'Tube amp with cheap transformers 'useless'?'
 
The discussion has ranged far from the topic as stated. I have tried to show that the arguments regarding profit margin are largely spurious, because these were raised as a justification for prices, but they are a side issue.
 
Setting issues of profit margin aside and regardless of absolute prices, there is no reason why a tube headphone amp with comparatively cheap transformers should be considered 'useless'. Why everybody seems determined to argue the contrary is a mystery to me, but I do notice amongst the respondents a commitment to tube amp ownership or involvement in tube amp production.
 
Here is a 3W Hammond SE OPT with a -1dB response from 100Hz to 15kHz which probably has a -1dB response extending from 20Hz to 50kHz when operated at a low DC bias and a maximum of 300mW output power. You can buy 2 for $70 US. http://www.tube-town.net/ttstore/product_info.php/info/p3197_Hammond-125ASE-Universal.html
 
Maybe I'll buy a couple of these. I've got a dozen Russian double triodes here I bought to mess with, run a couple of AC wallwarts back-to-back to get some HT. Try to remember some of that tube stuff I did in school in the '60s.
 
Note nikongod's comment when he is defending his design, not disagreeing with me:- About the only thing that goes below 60hz is organ music. IME most bass in pop music is in the high 50/low 60's. 
 
w
 
Talk's cheap, but it takes money to buy whiskey. I don't see a queue of people saying 'I'll take that bet.' First come first served. $100 to the charity of the winner's choice. No syndicates.
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