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Diago LS01 - 5w 9v amp?

Started by joecool85, June 19, 2012, 11:45:55 AM

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joecool85

http://www.musiciansfriend.com/amplifiers-effects/diago-ls01-little-smasher-5w-guitar-amp-head

Anyone have any idea what it uses for a chip?  Also, I doubt the 5w rating considering it asks for 9vDC @ 600ma which is only 5.4w...must be a VERY efficient design, no?
Life is what you make it.
Still rockin' the Dean Markley K-20X
thatraymond.com

tonyharker

Probably a Class D chip with linear preamp. Horrendous price though about $/£190 :-(

joecool85

Yeah, I'm curious what chip.  Also from sound clips on youtube it's nothing special, sounds like an LM386 circuit - at least when using gain.
Life is what you make it.
Still rockin' the Dean Markley K-20X
thatraymond.com

J M Fahey

It *must* use a bridged output chip, and as was hinted, *very* probably a Class D type.
No way you can pull 5 *audio* watts out of a 9V 600mA PSU.
Price is madness, but they may sell a few based on their novelty value.
Mind you, being a recording you have no idea of actual loudness; anyway they *only* plug it into very loud boxes: a regular Marshall 4 x 12" or boutique 2x12" with Vintage 30 clone ... and the drummer stays 10 feet further than the amp.
Anyway, nice idea and the sound is good.
Probably some *good* distortion pedal into a chipamp.

joecool85

Quote from: J M Fahey on June 23, 2012, 05:50:59 PM
It *must* use a bridged output chip, and as was hinted, *very* probably a Class D type.
No way you can pull 5 *audio* watts out of a 9V 600mA PSU.
Price is madness, but they may sell a few based on their novelty value.
Mind you, being a recording you have no idea of actual loudness; anyway they *only* plug it into very loud boxes: a regular Marshall 4 x 12" or boutique 2x12" with Vintage 30 clone ... and the drummer stays 10 feet further than the amp.
Anyway, nice idea and the sound is good.
Probably some *good* distortion pedal into a chipamp.

Totally agree except that bit about the sound quality using a good distortion pedal.  It's not bad, but in my opinion it is ok at best for the distortion in that clip.  Like I said, sounds like a LM386 at full tilt.
Life is what you make it.
Still rockin' the Dean Markley K-20X
thatraymond.com

tonyharker

So who's going to buy one to pull to pieces :) :)

joecool85

Quote from: tonyharker on June 25, 2012, 10:48:12 AM
So who's going to buy one to pull to pieces :) :)

I vote that you can do it  :lmao:
Life is what you make it.
Still rockin' the Dean Markley K-20X
thatraymond.com

J M Fahey

I'm sure it's not easily clonable, it must be all SMD construction.
But as I said before, the actual sound must be not too difficult to clone.
A few comments on what I saw:
1) repeat that it was "helped" a lot by pligging it into good, loud cabinets, not the cheap light 6" (best case 8") speaker you find in typical beginner level amps.
That alone accounts for 90% of good tone.
Demoers also used good guitars.
I liked the PRS very much.
And most of them played quite well, at least the short licks shown.
2) amazingly, the controls worked *very little*, definitely not the +15/-30db they claim.
Not in your wildest dreams.
On a 0/10 scale, they move treble from 3 to 8 or 9 ... very little effect.
The range they claim would have gone from mud to screeching ... and we hear noting like that.
3) shockingly, the gain pot has very little effect, and what's worse, even on 2 it fails to clean the sound, which remains crunchy.
No clean setting (at least none shown) from that pot.
On the contrary, the sound cleans to sparkly bright when the *guitar* volume pot is lowered, which makes me think that besides the distorting stage proper, the input stage (before the gain pot) is already very easy to overdrive.
I wouldn't be surprised at all if the distortion/preampo were a DSP chip, instead of analog circuits.
A friend of mine bought a very good sounding "Matal" distortion, which has 3 knobs: Bass, Treble and Output Volume, NO gain pot (it's always on full tilt).
Being curious I opened it to take a peek: it has only a solitary square 16 pin per side DSP chip and little else.
But the sound is definitely clonable.
We are getting into Winter, now I know what to do on those long rainy cold nights.
Stay tuned, I'll show it here.  8)

joecool85

Juan, not sure how much you've played with the LM386 circuits like the Little Gem, but they react exactly as you have explained - especially the bit about gain.  It never gets truly clean until you roll back the guitar for instance.

We're just getting into the heat of summer here, but stacking wood for next winter  :tu:
Life is what you make it.
Still rockin' the Dean Markley K-20X
thatraymond.com

maloushe

Gents,

James from Diago here.  I've been a member of the forum since early 2009, and a lurker for a lot longer than that.  Teemu's book is amazing.  I've learned a lot.

In response to your questions:

1) For the power amp, we're using a TDA7240A in bridged mode.  Into an 8 ohm load, we can get about 5W out of it; nearly 7W into 4 ohms (not clean).

2) For the best recording, see here: http://www.youtube.com/watch?v=Cablnl3Ag7Q  Do you really think that it's no better sounding than an LM386 based circuit?  That doesn't seem to be the opinion of most people who have heard it or played it.  I've built a bunch of solid state pre-amps and amps over the years and making a great one takes a great deal of hard work.  I'm really surprised you're comparing the LS with the LM386 based amps.

3) Pricing is a function of manufacturing cost, reasonable profit and the long distribution chain in this industry.  In the UK they retail at £99, including a power supply, which is much less than a lot of much simpler and less costly distortion pedals, without a power supply.  Do you think that it's wholly unreasonable compared with anything else?  If so, what do you think would be a reasonable price?

4) It's entirely analogue using a bunch of carefully designed op-amp gain/filter stages - think Sansamp approach with some more work.  Yes, it's almost all SMD.

5) Absolutely, it sounds the best through some decent speakers, and a decent cab.  Don't all amps?  That's one of the premises - most smaller amps are coupled with cheap crappy speakers, and people wonder why they don't sound so great...

6) The EQ controls are +15/-30dB.  On higher gain settings, they don't do as much, since a lot of the distortion is post EQ.

7) The gain pot is as I designed it.  It's voiced to give a plexi vibe, and with single coils it cleans up reasonably well.  Yes, with higher output pickups it's very easy to overdrive, just as intended.  I appreciate your criticisms, but it isn't designed to be the world's most versatile amp.  That's not what most people want.

If you absolutely must clone it, then I respect your freedom to do that.  However, Diago is a tiny company (just 3 of us), and I'd like to think that you may consider our business and livelihoods in the process.  I don't know what effect having that info in the public domain will do, but I ask that you consider the possible effects on us.  I appreciate that doing it has negligible effect on the larger organisations.

I'm happy to answer as many questions as you like.  Fire away../

If some of the more experienced of you have any advice, I'm happy to listen/read.

:tu:

James @ Diago.

joecool85

Quote from: maloushe on July 02, 2012, 01:16:41 PM
Gents,

James from Diago here.  I've been a member of the forum since early 2009, and a lurker for a lot longer than that.  Teemu's book is amazing.  I've learned a lot.

In response to your questions:

1) For the power amp, we're using a TDA7240A in bridged mode.  Into an 8 ohm load, we can get about 5W out of it; nearly 7W into 4 ohms (not clean).

2) For the best recording, see here: http://www.youtube.com/watch?v=Cablnl3Ag7Q  Do you really think that it's no better sounding than an LM386 based circuit?  That doesn't seem to be the opinion of most people who have heard it or played it.  I've built a bunch of solid state pre-amps and amps over the years and making a great one takes a great deal of hard work.  I'm really surprised you're comparing the LS with the LM386 based amps.

3) Pricing is a function of manufacturing cost, reasonable profit and the long distribution chain in this industry.  In the UK they retail at £99, including a power supply, which is much less than a lot of much simpler and less costly distortion pedals, without a power supply.  Do you think that it's wholly unreasonable compared with anything else?  If so, what do you think would be a reasonable price?

4) It's entirely analogue using a bunch of carefully designed op-amp gain/filter stages - think Sansamp approach with some more work.  Yes, it's almost all SMD.

5) Absolutely, it sounds the best through some decent speakers, and a decent cab.  Don't all amps?  That's one of the premises - most smaller amps are coupled with cheap crappy speakers, and people wonder why they don't sound so great...

6) The EQ controls are +15/-30dB.  On higher gain settings, they don't do as much, since a lot of the distortion is post EQ.

7) The gain pot is as I designed it.  It's voiced to give a plexi vibe, and with single coils it cleans up reasonably well.  Yes, with higher output pickups it's very easy to overdrive, just as intended.  I appreciate your criticisms, but it isn't designed to be the world's most versatile amp.  That's not what most people want.

If you absolutely must clone it, then I respect your freedom to do that.  However, Diago is a tiny company (just 3 of us), and I'd like to think that you may consider our business and livelihoods in the process.  I don't know what effect having that info in the public domain will do, but I ask that you consider the possible effects on us.  I appreciate that doing it has negligible effect on the larger organisations.

I'm happy to answer as many questions as you like.  Fire away../

If some of the more experienced of you have any advice, I'm happy to listen/read.

:tu:

James @ Diago.

Hi James, thanks for responding, this is all very insightful and helpful.  As to your questions:

1) If you are getting 5-7w, how can you only call for a 9v 600ma PSU (5.4w)?  By looking at the datasheet it looks to me like you should get about 3.5 - 4w at 8 ohm and 6.5w or so at 4 ohm on 9v.  If you are going with a 9v PSU you would really want about 900ma for 8 ohm and 1.5amp for 4 ohm output, otherwise you will be sagging your PSU and not getting full output.  With a 600ma output I'd be surprised if you end up with more than 2.5w or so.  Maybe this sag is part of the sound which is fine, but if that is the case, it can't truthfully be marketed as a 5w amp.

2) Wow, that is a great sounding recording!  I had found another clip on youtube and wasn't impressed at all.  I may have mis-judged the sound of it prematurely.  Is that a FET based preamp?

3) Price wise it's pretty expensive to me for a tiny head.  $190 USD from Musician's Friend.  For that same money I could get a Dean Markley DM30RC combo amp that sounds great, is 30w RMS, has two channels, spring reverb, chorus, well...you get the idea.  Back when the Epiphone Valve Jr was for sale, it was a 5w tube head that went for $150-200 depending on where you looked.  I think its hard for people to swallow the price when it is "just" a solidstate head, not a tube piece.  You mentioned manufacturing costs, where is it manufactured?  If its not in China, Korea, India etc, maybe mention it's place of manufacture as a selling point.  I'd like to see it sell for $125 - $140 if made in China etc, or if made in USA, Canada, England (or other parts of Europe) I would pay as much as $175-200.

As for suggestions, primarily I would complain of it's lack of headphone jack.  For such a tiny/compact little guy, a headphone jack should be a must.  Make it 1/8" stereo because that's what people will use anyway and it will save space.  You could also design the headphone jack so it could be used as a line out and people could even gig this little guy if they liked it enough.

Also, if it is built in a non-sweatshop environment, market that - it's a big selling point - seriously.

Good luck, and please come back, it's great to have industry insiders on here.
Life is what you make it.
Still rockin' the Dean Markley K-20X
thatraymond.com

J M Fahey

Hi James/Diago.
Congratulations on designing and building a *very* good sounding product.
In my book, that's the main point.
The fact that the physical design is cool , only adds to its desirability.
The Ferrari Red paint definitely does not hurt. ;)
So you got to sell it at major Music Shops, both in USA and the UK?
(Not forgetting other Countries)
Incredible !!
I fully agree that the Distribution chain is long, has way too many parasitic stages, and all of them multiply price by a lot. Unfair.

Speaking for myself, please take my comments with a grain of salt and consider them made in good faith.
Not knowing *anything* about your amp or background, all we can do is guess.

Thanks again for being so polite and using some of your valuable time for writing us.

Congratulations again on a great sounding (and looking) product.

PS: *if* you could enlighten us on anything you think useful or interesting, such as your approach to manufacturing, or some short explanation on distribution channels or whatever, we would be very grateful.
It's a kind of experience far removed from our daily one.

PS2: and please tell me that the 600mA rating from the PSU is *very* conservative.
I do not doubt your power rating, the datasheet also confirms it, but I'm calculating a higher current need.
Not a criticism, quite the contrary, maybe your PSU is *way* overbuilt .
:dbtu:
Good luck.

joecool85

Quote from: J M Fahey on July 03, 2012, 12:41:10 AM
Hi James/Diago.
Congratulations on designing and building a *very* good sounding product.
In my book, that's the main point.
The fact that the physical design is cool , only adds to its desirability.
The Ferrari Red paint definitely does not hurt. ;)
So you got to sell it at major Music Shops, both in USA and the UK?
(Not forgetting other Countries)
Incredible !!
I fully agree that the Distribution chain is long, has way too many parasitic stages, and all of them multiply price by a lot. Unfair.

Speaking for myself, please take my comments with a grain of salt and consider them made in good faith.
Not knowing *anything* about your amp or background, all we can do is guess.

Thanks again for being so polite and using some of your valuable time for writing us.

Congratulations again on a great sounding (and looking) product.

PS: *if* you could enlighten us on anything you think useful or interesting, such as your approach to manufacturing, or some short explanation on distribution channels or whatever, we would be very grateful.
It's a kind of experience far removed from our daily one.

PS2: and please tell me that the 600mA rating from the PSU is *very* conservative.
I do not doubt your power rating, the datasheet also confirms it, but I'm calculating a higher current need.
Not a criticism, quite the contrary, maybe your PSU is *way* overbuilt .
:dbtu:
Good luck.

Juan, even though the unit says 9v 600ma, the PSU that comes with it is 9v 1,000ma according to what I read online - I had missed that before.  That's pretty reasonable.
Life is what you make it.
Still rockin' the Dean Markley K-20X
thatraymond.com

maloushe

Joe, Juan, everyone else,

1) Yes, it comes with a 1,000mA PSU.  The 600mA is a conservative nominal rating (under most usage conditions), although we should probably be a lot more clear about that.

2) The pre-amp is all op-amp based (TL2262/4s). No FETs at all.  AMT Electronics use FETs and their products sound amazing.  I'd like to know more about how they di do it...

3) Joe, I'm presuming you're in the US?  I understand your sentiment.  Pricing is an important subject, and there are a lot of decisions to make along the way.  If we use your comparison, the the LS seems like poor value.  However, if you compare the LS with a Fulltone OCD (just for example), the result is different.  The Fulltone OCD could be made for about $10, but it retails at the equivalent of $300 USD in the UK.  Comparing the BOM cost and complexity of the OCD vs the LS, and the LS offers much better value for money.  As a tiny business, we're not able to compete sharply on price, and we're not aiming to do that alone.  Of course all products are price sensitive to a greater or lesser degree, but our aim is to offer new concepts, and better things.  That's where we're able to compete with the bigger boys.

As a new concept and product design that cost us a lot in R&D time and a reasonable amount of money, we thought it was a reasonable price.

Also, our focus is on quality; for example the casing is 2mm / 14 gauge steel.  We could have made it from a much more lightweight material that would have done the same job, but I  like to take things that bit further to give the best overall experience and reliability.

One other problem in this industry is that US brands often self distribute in the USA.  US brand products are often way cheaper, since they add no distribution margin in the US, hence the Dean Markley problem.  Outside the US the prices are typically 50-100% more than they are in the US.  In the UK the Fulltone OCD (again, just an  example) is the equivalent of $300 retail, with a street price of $200.  It's $135 in the US.  Our products have a relatively flat pricing structure throughout the world, since we use the same business model everywhere.

4) We manufacture in China.  The dreaded C word!  There's a blog post on our website about it, but I'll cover some of the main reasons here.  Originally I had our pedal boards contract manufactured in the UK.  I had a lot of trouble with the supplier (late delivery, not able to deliver the quantity we required, quality issues, changing of specification with no warning or agreement, etc., and i tried to find another better factory, but to no result.  I simply couldn't find any one interested in that kind of work.  The biggest issue was getting anything more than a wooden box made - most factories just wanted to do one element or type of work, but I wanted someone to manufacture and supply a complete, finished product according to our design & specifications.  Eventually I contacted a rapid prototyping company in China that I'd had some dealings with making CNC parts for industrial pumps, and who had been amazing to deal with.  I had found them a few years earlier via mfg.com as part of my previous job at the pump company and asked them if they knew anyone who could help.  They told me to go and see them and that they would help me.  I flew to China, they took me round 5 factories that they had arranged meetings with, and we selected one.  Before I went, my friends asked each factory to make a sample.  The factory that we selected made a great sample, understood the product requirements, and went out of their way to listen and help.  I've never had service like it anywhere.  They still make our pedal boards now, 4 years later, and I'd say that I'm very good friends with the factory owner.  She's a great lady.

Anyway; the summary is that China was never specifically on the cards.  It was just the result of me asking a good supplier that I knew, if they could help, and they did.  Now, I can get a finished product (packaged, including everything) made to a design and specification, without too much fuss.  Sometimes there are things to clarify and sort out, but on the whole, it's straight forward to manage.

Prices are generally in the region of 20% cheaper than a UK BOM + assembly cost, but when you factor in shipping there's not actually that much difference to justify the remoteness and lack of control.  The simple fact is that, in my experience, it's much easier to get things done the way we are doing it.  In general, manufacturing is done on time to our QC specs.  Development is mostly straightforward too, done by email and Skype.  It's surprising what can be done that way, and it's all documented.

So, going back to your original point Joe, I'm surprised that you'd be prepared to pay more if it was made in the West, than in China.  Can I ask why, in your opinion is it reasonable to pay more for something based on location of manufacture?  As we're both engineers, I can't understand why you would be willing to pay more for a Western made product.  Maybe it's better phrased as, what does a Western made product offer you that a Chinese made product does not, when the design, specification and quality is the same, that justifies a higher price?

Korea has similar overheads to the West, so Korean made product is only ever going to be cheaper if it's made more efficiently.

5) The Epi Valve Jr sounded like a bag of spanners. It sold simply on the merit of it being a "real" valve/tube amp at a knockdown price, what we'd call lip service in the UK.  I appreciate what you're saying, and I find it interesting that people have this hierarchy of price / location of manufacture / tubes vs solid state / etc. going on in their heads that has this rigid structure that they can't get away from.  I have come across quite a few people who simply cannot bring themselves to buy a better sounding SS or DSP amp over a crappy sounding tube amp at the same price.  They do not believe their own ears, or do not want to.  The good news is that the web and a new breed of younger players is helping to change this, at least in certain sectors of the market.  They're learning to buy with their ears, not their eyes or by specification.

6) Good suggestions.  A headphone jack and line out is something we've be asked for a thousand times...and another thousand have asked "can it be plugged into a desk / DI box?!"  The LS  was a first product of it's type (I mean for us, our first electronic audio product), so we kept it relatively simple and manageable (financially and project wise).  We have plans to take the concept further, using some of the functionality of larger regular amps.

7) Sweatshops....  I've been to our factories a few times, and they're definitely not sweatshops.  Folks in China have different expectations of work than we do here - sick pay, holiday pay, health insurance, are not expected.  Chinese people expect to sort that out themselves from their own pay, and it comes from their views and culture of self sufficiency.  That is, however, changing very quickly as the economy develops and the workforce evolves.  The Chinese do tend to work harder and longer hours than us in the West.  This, again, is a cultural difference as much as anything else; their days and weekends are not set-out like ours.

I like the idea of marketing the fact that our factories are not sweatshops, if that's of great concern to buyers.  However, I'm not sure how we could/would go about it - photos of the factories on the website perhaps?

8) Yes, our products are now available in about 30 countries.  Have a look at the "Where to Buy" section of our website.  We design the products here, everything from concept, electronics, PCBs, mechanical design, artwork, packaging (including the box nets), and website.  Designs and samples are sent to our project manager in China and she goes about sourcing all the parts, assembly and packaging, and supplies to us as a finished product.  We sell to distributors direct from the factories in China; that way we're not unnecessarily sending stuff around the world for no reason.  Orders to Australia for example go direct from the factory to the Australian distributor.  The distributor then sells the goods to the stores, and the stores sell the goods to the end users.  I'm sure you can imagine how much we need to be able to have products manufactured for vs the end user price and how little of that actually ends up our pocket.  I'm not playing my miniature violin, and accept that this is how it's done (at least for now), just pointing the issue out.  Even if we made a 50% margin (which we don't get anywhere near), both a distributor and a retailer would still make double what we make on any given product; each.

From a environmental point of view, since we're selling all over the world, it makes no more sense to make the stuff in the UK than it does in China.  Wherever we make the products, some customers will be close by, and some will be at the other side of the world.  I calculated that the shipping cost (just the freight element, no taxes etc) for sending a Little Smasher from China to the UK is about 0.04GBP, so about 0.06USD.  By definition, the fuel cost must be less than that, and it's the use of fuel that causes the environmental issues.  If you compare that with me driving to a local music store (10 mile round trip, vs 6,000 miles), to buy something, you'll agree that shipping stuff around the world by sea is insignificant and that there are far better and significant ways to reduce the impact of transport on the environment.  Shipping by air is another matter...

I hope that's interesting.

Keep firing questions at me if you have them.

:tu:

James @ Diago.

joecool85

#14
Quote from: maloushe on July 03, 2012, 02:45:40 PM
Joe, Juan, everyone else,

....

Keep firing questions at me if you have them.

:tu:

James @ Diago.

First, again I have to say thank you for taking the time to talk to us here, it is really cool to have someone doing what you are speaking to us in plain terms about how it all works.

I am in the US as you presumed and pricing is very important.  The reason I would (and do) pay more for items made in North America, Europe, then elsewhere is somewhat complex.  I like to keep money local, this is especially important to me when I can buy something made in the US as that means it is helping support workers in my country as well as that company paying taxes to my government.  Past that the reason I like to buy within North America etc is primarily due to quality and shipping. 

Quality, in my experience, tends to also be better from those countries of origin and lesser from China, Korea, Indonesia etc.  Shipping is also important as I have a hard time justifying purchasing something made in China when I know it could be made right here and not be shipped from the wrong side of the planet.  That said, I do appreciate (and honestly hadn't really thought about) the fact that as a business if you are manufacturing products in one location but selling them world wide it is a moot point as far as shipping.

As for the pricing in comparison to amps or pedals, that needs to be in your marketing.  If you want to sell it "as an amp" then it will need to be price competitive or feature competitive.  I would say the LS01 does this poorly...moderately at best.  If you want to sell it "by sound" similar to a pedal, then you have a great chance at success.  I would push the tonal quality, build quality and innovation of it more than anything else.  Market it like people market pedals and you will be much more likely to get the returns you are looking for.  IE - "Great sound, killer overdrive" rather than "5w amp with 2 band EQ".

As for the product evolving, like I mentioned before I would love to see a headphone/lineout jack.  Honestly though, I wouldn't take it much further than that.  The LS01 has a beautiful simplicity about it and I think that in itself is a huge selling point.  Plug in and crank out the tunes, that's not always an easy thing with a full featured amp.

If you do decide to make a more feature filled mini-head, I would make it as it's own model...maybe the LS02.


Quote from: maloushe on July 03, 2012, 02:45:40 PM
As we're both engineers...

While I appreciate the compliment, I'm not actually an engineer.  I have been labeled as a "fun-gineer" by my Civil Engineer brother though.  Electronics are just a hobby for me.  I am an IT Manager by trade and I do web development and electronics repair on the side.
Life is what you make it.
Still rockin' the Dean Markley K-20X
thatraymond.com