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I've got 8 ohm single drivers and would also like to add 16 ohm Zu's to the party. Looking at an integrated Yamamato 08 (no S, AC heated before went to DC) or a Loften White circuit. Not really sure which one would suit me best.
Please tell me if anything on my wishlist is unrealistic... was hoping for two inputs, one for dac and another from a phono stage, both 8 ohm and 16 ohm outputs as well as a headphone jack to be used with Senn 600/HifiMan 560. The headphone component can just use resistors or whatever it takes to match up with the phones, the speaker outs are the main focus. And lastly volume control so no preamp is needed.
Does this sound doable? This will have to be a fairly medium of the line build so no crazy expensive parts, any iron suggestions for this?
Is the Yammi circuit direct coupled to the output transformer? Does this design both offer both plenty of detail and harmonics? I'm looking at the Yammi over the Korneff circuit for the supposedly more gain. How does the Yammi circuit differ from a Loften White circuit in terms of listening experience? Perhaps I should be looking in this direction? I'd like to eek out every last drop of detail while still having tone and harmonics. Ultimately I guess I'm looking for an emotional euphonic amp but with realism and detail.
Anything else I should consider before progressing with a build?
Thanks
Follow Ups:
Don't listen to voodoo.
And don't paste "voodoo" labels on good engineering that some experts don't understand.
---Dennis---
Don't forget the Bottlehead kits- I understand the Parabee can be built as a direct coupled 45, and I think the Stereomour can also be built as a 45. Search the archives of their forum.
Don's stuff is off the charts AFAIC. If you can wait that long- maybe a stereomour would be an interim option.
For clarity, Parabee has been out of production many years. Paramount, Bottlehead's 300B/2A3 amp, has been built as a 45 by some customers but that is not a standard part of the product.
Stereomour is at present available as either a 2A3 or 45 amp, as an option in the standard product.
I am for the Bottlehead products-I have 2 Stereomours 1 a 45 the other a 2a3 and also Bottlehead 45 design amp --all are parafeed . I highly recommend their products. They have great instructions for your builder and great backup on their forum- and of course the sound is excellent they are easly tweaked either as you build or afterwards--howie
Are you buying, building (DIY) or having the amplifier built by custom builder?
There are not many mfrs. Yamamoto and Don Garber are the only two that immediately spring to mind and Audio Note, but Don only builds a power amp. (unless he makes X-45) and you will have to wait around 2 years or more to get it from Don. The Audio Note I am thinking about,the Paladin, is a stereo amp, but not an integrated and it is cap-coupled, like the Yamamoto. Don's 45 power amps are direct coupled.
OPTs are really important with SET. Don goes back and forth; I'm not sure what he is using now, but he works with his customers on that. The Yamamotos have C-Core OPTs. The Audio Note 45 comes, standard, with EI OPTs. For more money you can buy the Silver or Silver Signature models of the Paladin, which sport different dual C-core OPTs.
I have an Audio Note 300B Conqueror, Silver, which is the 300B counterpart of the Paladin Silver and these OPTs make a significant difference over the EI OPT in the standard models. That said, I've listened extensively to the Standard Paladin and it's a nice sounding amp. However, I prefer the 45s I am running in Don's 2A3 monos; the only changes i make are to the rectifier tube to do this. It's not optimal, but Don says it's pretty close. I use Magnequest QS-025 OPTs, which are EI construction with interleaved secondaries. They are very good.
An excellent, custom 45 amp will probably cost around $8K-$10K (and up) from a "reputable" builder. I haven't looked into the low-end ($-wise) of custom builders. Well, I have, but the guy i was lucky to find - Jef Larson - is retired and sold off his parts.
Good luck. The 45 is a great tube, just as previous posters have noted.
One more thing. DC amps tend to be a little noisier than cap or transformer coupled amps, but not real noisy.
I forgot one commercial builder, Eddie Current. He builds a transformer coupled headphone/speaker 45 amp, but I think he's gone to parallel 45s on his 45 model. His prices are very reasonable. (So are Don's), by the way. He (Craig Uthus) has a web site by the same name (Eddiecurrent.com).
Good luck again.
Observe, before you think. Think before you open your yap. Act on the basis of experience.
Thanks Frihed89
So I'm having someone build this for me but not by a 'reputable' builder as my budget doesn't allow it. Anyways I think I found my guy. He is just more affordable than any of these other options including Don. I heard a Jeff Larson 2A3 and that's how I fell in love with the set sound. I might just go with the knockoff yammi and see what I think and take it from there.
Here's a trick question, a cap coupled 45 like the yammi vs a direct coupled loften white 2a3 like Don's?
The two stage direct coupled Type 45 amp should be superior to a two stage cap coupled A-08S.
Two reasons :
( 1) The direct couple is simpler, superior to a cap couple.
(2) A triode driver tube is simpler, superior, to a pentode driver tube.
Be sure the DC amp uses a mu of 100 driver tube.
Why a Mu of 100 rather than Mu of 35 or 70? Even a mu of 35 will drive the amp to full output.
Thanks drlowmu
2 Q's
A- Will using a triode driver tube result in less gain? Any negatives of going this route?
B- Will a triode driver tube build be more costly than using a pentode driver tube?
Cheers~
Not if you use a high mu ( high gain, gain of 100 ) triode, as is often done since 1947 in better L-Ws.
( eg : 6SF5, 1/2 of a 12AX7, 7B4s, etc ). All triodes, simple linear.
The Pentode takes more parts to implement.
something like the 6SF5 single triode driver ?
Yes, that driver tube is what Robin and Lipman published in 1947, 6SF5 DCed into a 6B4G. .
Better driver tube choice is 1/2 a 12AX7, it is plentiful, so you can "tube roll" ( Telefunken smooth plates, Amperex, Mullard, etc etc etc. )
Additionaly, I discovered in 2014 that higher mu triodes that are octal based ( 6SF5, 6SL7 ) SUFFER slightly, just from having eight soldered connections, to the Octal pins, that is HEARD as a degrade in ultimate clarity and resolution, compared to a more modern 9 pin miniature triode. Diction suffers, ultimate resolution suffers on voice.
I have A-Bed this. With the better tube-type choice, its extra clarity for free, IF you are conscious to make the best tube choice decisions at the onset. You can sub 1/2 a 12AX7 for a 6SF5, not any problem what so ever.
If you contact me privately, via email, I can send you information and suggestions to directly apply to your Type 45 build, …..IF… you elect to do a DC amp. I can even refer you to others using Type 45s, I have helped.
Its not "for peanuts" that you build an amp, but I am an amateur and I advise for free. I know I can provide you the best bang for the buck in performance suggestions, that will fit within your tight budget. I have enough experience to do that.
Jeff Medwin ..... email address above
actually I just looked on the original schematic from 97 and Tucker used the Medium Mu twin triode 5965
I do NOT wanna critique Messers. Tucker, Garber, Uthus on a public forum. Lets do an email discussion !!!Jeff Medwin
Edits: 12/17/14
Hi Jeff
Sounds good I would love you hear your experienced thoughts and don't want this to turn in to an emotional forum debate so I will contact you by email. What is your email address?
Cheers~
Click on my Moniker, ( drlowmu ) and it leads to email address .
Jeff Medwin
I really like my Fi Amps. I haven't heard the Yamamoto. I have heard a lot of cap coupled 300B, 2A3 and 45 amps. I have owned 2 cap-coupled 300B amps and a 2A3 headphone amp and enjoy(ed) them all. I still have one of each.
It's all in the design and parts, either way. I am particularly struck by the need for excellent OPTs. I've already upgraded my Fi OPTs and will do more when I have the money. My Audio Note 300B amp already has double C-Core Hi-B transformers, not the best, but quite a bit better than the standard cores.
So, I'm going to beg off.
Good luck.
Observe, before you think. Think before you open your yap. Act on the basis of experience.
Hey TAdams,
Just a couple of questions and observations:
1. Is this your first build? If yes, please do a web search on safe practices..can't enjoy your work if you're lying dead in a puddle of piss.
2. keep it simple. A DC couple amp with multiple inputs and the ability to drive a load like headphones for a first build is a bit ambitious. Others on the forum might encourage you...obviously your choice.
3. There are simple RC or IT coupled designs out there that will let the magic out. I found Parafeed fairly simple to implement with a little tweaking of the cap. You can achieve a good sounding quiet design and leave room for more complexity in the future.
4. Prototype the amp on a board. Just keep kids and pets away.
5. After you're happy with the prototype, move to chassis and follow good mounting an grounding practices...just search this forum. Then you work on a quiet build.
6. A good middle of the road OPT that I like is Lundahl SE LL1663 5K primaries gapped for 50mA will do nicely. Around $350.00 for a pair. They are C core and ugly, but good sounding. You will want to hide them...
7. With 2 glorious watts to work with, your speaker drivers will need to be at least 98db/watt efficient. You can go less efficient in a crutch. You will loose much of the magic though...
Good luck...use this forum, ignore the bickering..many of our members are suffering from low "T" and tend to bicker like women...;> )
Stuben
Hi Stuben
I don't build amps so I am having someone build this for me. I have someone in mind but if anyone wants to put their name in the hat then right on.
Cheers~
If you are having this built on spec, you will get what you asked for. It may or may-not sound good. It seems to me that you need to audition some amp designs and then decide which is for you and then have it built. The volume pot and selector switches are just add-ons and no real problem for a builder.
In my experience, the output xfmr and gain/driver tubes are the most important considerations to the design. Nickel core outputs are the best IMO. Early radio tubes, 37, 76, 6C5, 6C6, 6F8 ... are my favorites for gain/driver, 6SN7 and 6SL7 are also good.
Consider contacting Dave Slagle for nickel outputs. He is a member here, and he is also a friend ( to be upfront about it ) and an avid builder.
Thanks for the input Gents I really appreciate it.
Hifi Paul: I agree I should do some auditioning. I live in Edmonton Canada. Any SET heads around here? Perhaps I should do a separate post inquiring. I also would not like to go on spec but have someone who will tweak a circuit to something special.
Frihed & Amioulatine: I am getting more interested in the Simple 45 parafeed with Magnaquest iron. In particular I read Bill Epstein's article on the build he did in conjunction with Steve Brown in 07. So unless there are any major objections I think this is where the journey will lead off to at this point. Are Steve and Bill still around for input?
http://dagogo.com/the-simple-45
http://www.positive-feedback.com/Issue1/single.htm
http://www.audioasylum.com/cgi/t.mpl?f=magnequest&m=5599
"The unparalleled linearity of the 45 tube (1930’s National Union) together with the bandwidth of Mike Lefevre’s Robin Hood transformers and a touch of romance from Brian Cherry’s Obbligato oil caps combined to bring a life to all the music we played like I have seldom heard."
I think the simple 45 with Magnequest output transformer is a great place to start and a very simple project for the builder. I would use a K & K CCS on the first tube and a Magnequest DS 050 for the output transformer. The first tube can be any of the 12AT7/12AV7/6N1P varients (like the 5965). Don't forget that with 2V coming from the CD player or phono stage and a bias voltage of -56V you only need a gain of 28 to drive the amp to clipping. If we add 3dB for headroom, you still only need a gain of <40 to drive the amp to clipping. That's not much of a challenge.Don't get bogged down in audio dogma. Keep it simple and worry about boutique parts later. Those are things you can change or experiment with yourself once the amp in built. If you start with an excellent output transformer and a chassis with plenty of space, you can mess with it for years.
Edits: 12/17/14
I use a cd player to a Grant Fidelity Tube Dac 11. Using the tube buffer and volume control it's 2V and using the straight dac out with no volume control (and more transparent) it's 6V so I guess I should take this in to consideration as well? Down the road I might get a new dac but that won't happen for years or unless it fails.
Yes, the Grant Fidelity Tube Dac 11 documentation leaves a lot to be desired, but it appears as if the "DAC out" is line level, e.g. 2V and the the tube "buffer" and volume control with the added gain stage of the tube has an output of 6V. That said, I think you will find the best sound if you put the volume control (100k audio taper) on the front of the amp and use the DAC line out. 2VRMS line output is the standard "Red Book" value so you don't need to worry about future CD player or DAC purchases.
I build all my amps with an expected 2V RMS input, so I actually try to have the amp clip with a 1V input to give myself 6dB of headroom, but it is not always possible to achieve this with a two stage amp which is what you are considering. As I stated above, with 2V into your volume control and the 45 tube clipping with 56V at the grid, it should be simple to engineer a two stage amp.
Well This is the SET forum and not the DIY...My bad.
Many say the DC coupled amps are quite magical..
Check out Paul Joppa's thread on the DC coupled 2a3. Very generous guy...
Stuben
Emotional and euphonic just isn't in the 45 tube. Truth in tone and timbre are the hallmarks.
My search for an affordable 45 build after first hearing the original Yammamoto 10 years ago ended with my current John Tucker designed amp which I feel betters the A-08 in bass weight and tone.
At the request of the Moderators,
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"Truth in tone and timbre" sounds good to me. I hadn't heard about the Tucker direct coupled parafeed amp but it looks interesting and will keep that in mind. Any negatives to going parafeed? I also like SET bass and the result in an appropriate speaker.
If you build the Simple 45 look it up on the Magnequest Forum for posts with Pix (I don't have the means to post a link).
Steve Brown built mine; we used a dual mono design from the power transformer with a beefed up CCS and up-rated cathode resistor.
Some direct-coupled amps may tend to noise as Frihed wrote but this one, with 97 dB speakers, is absolutely quiet.
At the request of the Moderators,
This space has been deleted
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