AudioCircle
Industry Circles => ModWright Instruments (MWI) => Topic started by: modwright on 24 Sep 2015, 12:55 pm
-
We are preparing for RMAF as you know…
We are going to be unveiling some exciting new products:
845 DS - 32W SET amplifier, Cost No Object Mono Blocks!
Ambrose 10W SE EL34 stereo amp.
SWL 9.0 Anniversary Edition prototype preamp - to be released later this year (< $3K).
Damon Coffman Design (Coffman Labs) designed tube headphone amp - purely prototype - for customer feedback. (EXCITING NEW PRODUCT!!!) 2W all-tube headphone amp, also capable of driving efficient speakers. Ultimate headphone/desktop speaker amp!
We will be in the following rooms:
Iris Room: ModWright/WyWires/Daedalus.
Ambrose EL34 tube, KWA 150SE's, LS 36.5 'DM', Elyse DAC, PH 150 phono and Modified Oppo 105D.
8002: ModWright/Skogrand/Triangle Art Turntables/Massif Design wood racks.
845 DS Tube Mono Blocks fronted by LS 36.5 'DM', Elyse DAC, PH 150 Phono, and Modified Oppo BDP 105D.
422: ModWright/Purity Audio/Deadalus/Dynamic Design
Elyse DAC and PH 150 in use.
-
You had to introduce the 845 amps the year I can't attend. :evil:
I just hope the amps have enough headroom with the 91 dB E-5s. I know the cabling is good -- I got them.
Man, I wish I could spin my SRV 45's in this room.
-
You had to introduce the 845 amps the year I can't attend. :evil:
I just hope the amps have enough headroom with the 91 dB E-5s. I know the cabling is good -- I got them.
Man, I wish I could spin my SRV 45's in this room.
Just a plane ride away! ;)
-
Just a plane ride away! ;)
Sure, then it would be the last RMAF ever. :roll:
Next year, they are going back to Columbus Day weekend and I should be fine. Don't mess with your wedding anniversary. :rules:
-
Sure, then it would be the last RMAF ever. :roll:
Next year, they are going back to Columbus Day weekend and I should be fine. Don't mess with your wedding anniversary. :rules:
Rocky Mountains on an anniversary would be wonderful! ;)
-
I am not worried about the Endeavors. 91dB is plenty and they will sound fantastic! I am excited and we are going to have a great show!
Happy Anniversary!
Thanks,
Dan
-
Dan:
Congrats on your (many) new products! Sadly, I was unable to attend CAF this year to see/hear the Ambrose but it seems to have created quite a stir. Truth be told, while I am still very much in love with my KWA150SE, I could be tempted away by a pair of your mono blocks--though I do hope that down the road you are able to add a pair to the lineup that are priced for us mortals! BTW, which Dynamic Design cables will you be showing in Room 422? Have a great show. Hope to see you at CAF in 2016.
-
Hi and thanks. I plan to look at a line of products that are closer to the $3K range also.
The big tube amps are NOT cheap to make and certainly not to the standard that we have striven for.
The headphone amp will be in our more affordable line as is the SWL 9.0 Anniversary Edition.
Monoblocks I will have to see about. It is COSTLY to build the KWA 150SE and it is a FINE amp. It is hard to meet cost points without compromises, but it can be done.
Thank you for your support!
Dan
-
Dan,
Please email me with headphone info. Very interested. Just had my amp upgraded, but also very interested in some non $40K tube monos. 8) Good luck at RMAF, I am sure another excellent showing.
-
OK, here are the deet's.
It is a prototype and many things are still in flux. The following will be issued in a press release.
Tube Headphone Amp prototype (yet to be named) - Target price range = $2995
Tube complement: (2) NOS 6922 or 6DJ8 dual triodes, (4) NOS 12B4 single triodes.
BW: 20Hz-30Khz or better.
Dimensions: TBD (Still early prototype)
Power: Final is TBD, but capable of driving high efficiency speakers. 2-3 Watts or more.
Weight: TBD
Design details:
Circuit design by Damon Coffman of Coffman Labs design.
Shortest possible, all tube signal path design.
Vintage NOS OIP (Oil-In-Paper) coupling and bypass capacitors.
Single stage NOS 6DJ8 -based voltage amplifier into NOS 12B4 based P-P output stage, transformer coupled with custom Electraprint Phase Splitting Reactors (PSRs) and P-P output transformers.
SS voltage rectification for best overall sound and lowest noise (determined after extensive listening and measurement).
Choke current and voltage regulation.
Features:
(1) Mini jack output, (1) XLR balanced output, (1) 1/4” output.
One pair RCA inputs. (Possibly toggle for two inputs or selector for more - still TBD).
Volume control goes to ’11’.
Speaker Output jacks? TBD. At 2-3W, it could still drive high-efficiency speakers or desk speakers. (Input here welcome!)
Finish and Aesthetics:
Still TBD, but expectation is for well isolated, single enclosure design with small desk-friendly footprint.
A lot of details to be finalized. Target price is to be $3K. It will be a NICE looking piece of gear! Options will be determined by feedback from customers.
We may offer add cost options, depending on what options are desired, but we can cross that bridge.
I am thinking of a one-box design, dead quiet, with exposed tubes (removable tube cage) and retro/modern aesthetics with exposed tubes and modern finish. Still a ways to go in this department, but the CIRCUIT SPEAKS FOR ITSELF!
I will be offering after-hour demos in the Iris Room at RMAF with Audeze LED-X, HiFi Man HE1000's, lower price Hifi Man model and Ether 'can's. Wherever possible, Wywires custom headphone wire will be used for demos.
Anybody interested, PLEASE drop by at RMAF, or at least, please chime in with input here!
This is an exciting collaboration between Damon Coffman of Coffman Labs and ModWright Instruments (MWI).
Thanks,
Dan
-
Hey Dan:
Can you provide any update on the two new tube amps you recently debuted? Is it possible the Ambrose will be offered as switchable for use in monoblock pairs like the KWA150? Love to hear how things are coming along if you have anything to share.
-
Hi Guys, the Ambrose and 845 DS designs are both finalized and I am working on reviews for both.
(http://www.audiocircle.com/image.php?id=133340)
I just returned from Las Vegas where we further optimized the 845 DS monoblocks with a small adjustment to the design which further reduced THD by up to 75% and IMD by up to 50%. We had a great showing with the local Las Vegas audio society and the amps were very well received.
(http://www.audiocircle.com/image.php?id=133343)
The Ambrose as shown is a 10W stereo amp. We can also make a 20W stereo amp or 20W monoblocks. For that design, 20W is the maximum power that we can achieve from an EL34 SE design. The cost really depends on the finish of the enclosure. The 10W Ambrose as shown in DC and at RMAF is $9995 retail, with flamed maple and EXPENSIVE solid billet AL enclosure details. I know that we could offer the same design in a less exotic enclosure at a lower price.
(http://www.audiocircle.com/image.php?id=133341)
Both pieces were built as concept designs and I took the Ambrose to Capital Audiofest first and then the 845 DS mono blocks to RMAF and have been honestly waiting to see what market acceptance is for such designs.
I really need to know what interest there is in 10W, 20W and 34W SE/SET designs.
Thanks and I look forward to any/all of your replies.
Dan Wright
-
I really like the looks of the 845 DS amp. Looking forward to hearing more.
-
Hey Dan:
The new tube amp designs are beautiful and I am looking forward to seeing and hearing them, hopefully at CAF this summer. I wonder whether you might try the same approach with these as you have with your solid state offerings--a "basic" model in a less expensive aluminum enclosure styled to match your other gear and a "Special Edition" which would include an upgraded enclosure and (potentially) premium parts. I'm sure there are quite a few folks who would be willing to pay extra for the wood finish and higher grade metal work. You have a lot of people out there using your electronics with Daedalus speakers and the ability to select a wood finish for the amps to match their speakers would be VERY cool. A pair of mono blocks matched to the speaker finish would make quite a visual statement!
Maybe you could share a little more information about system matching with some of Lou's speakers? I've got the KWA150SE which is much loved driving my DA-1.1s with the AP and V2 upgrades. Based on what I've read about the 2015 CAF show, it seems that Lou's larger designs might like the additional power offered by the 845 monos but I wonder whether a pair of 20w Ambrose monoblocks would drive his full range systems (like mine) with authority as well. I really love the drive and ability to project that the KWA provides and do not want to loose any (much?) of that by going to a low powered tube design. But I have to say that your new creations have created a bit of tube lust in me. Have you had the ability to do much comparing of the new tube designs with your KWA 150SE's on the Ulysses in your shop? I think some of us who are happily using your solid state flagship would be interested in what can be gained by adopting tubes and would be interested in which model matches up best with the various Daedalus models.
-
Hi and thanks for the input. I agree that a Premium model and a lesser cost standard model makes sense. The circuit design would be the same, but the premium would be in the parts cost and enclosure.
I have only compared the 10W EL34 amp to the 150SE and it IS enough power, unless you are in a BIG room. The 150SE has a bit better control, but lacks the beauty of tubes that the 10W amp provides. I DID hear the 20W version at Jack Elliano's last week, compared directly to a 10W version and the presence and control was SIGNIFICANT! I am thinking that 20W monos simply make more sense all the way around. The 20W EL34 design would close the gap in terms of control, compared to the 150SE and still offer the beauty of tubes.
The 845's are the best sounding of the lot, in terms of presence, 3D soundstaging and the things that SET's JUST DO WELL! This also comes at a price however, because the tubes and 'iron' to create them are simply not cheap.
I will look into pricing a 'Standard' finish for the 20W monos as well as the 845 monos and see what I can come up with.
Thanks!
Dan
-
What brand/model 845 tubes do you use?
-
PSVane 845s.
Thanks,
Dan
-
Hey Dan, check out the Gold Lion re-issue KT66s. They're my favorite power tube as they combine excellent resolution, frequency balance, and frequency extension on both ends, with SET like refinement and immediacy.
Rob
-
Thanks, I will check it out!
Dan
-
Hey, Dan. Any update on the tube amps? What are the chances you will be bringing 20w Ambrose monos to CAF this year?
-
Hi, am still working out a design and pricing strategy for this. We have also found that we can build 36W monos with (3)EL34's and a single 12AT7 per amp. I will not be at CAF this year, but we MAY introduce a pair of tube monos (20-36W most likely), at Newport.
I am thinking that monoblocks in the 20W-36W range will be in the $10K-$15K/pr range (Not 845 designs). I just need to know how much interest there is in this type of product at this price.
Thanks,
Dan
-
Thanks, Dan. I hope that some other folks will chime in here in support of this venture. I would be very interested in what you have described (36w with 3 EL34s) to drive my DA-1.1s. Please keep us in the loop as you work out the final details of both your tube amp projects.
-
We have the design worked out. It is just a matter of demand.
Thanks,
Dan
-
I had the pleasure of auditioning Dan's Ambrose over the past month in my home audio system. We have had several conversations as to a direction that might well suit the goals I'm seeking for improvement over our current Simaudio W5. I can say that, although I've had the likes of Merrill Veritas, Pass XA 60.8, and Hegel H30 in over the past year, nothing has provided the midrange, imaging and staging that the Ambrose has. Its synergy with my Daedalus Athena is particularly captivating. It is also one of the most beautiful audio pieces I've seen - a true heirloom quality piece. The collaborative effort that has gone into this design is truly impressive - the EL34 is a special output tube. I look forward to the possibilities of a 36w monobloc version.
-
Plans for a 30W+ EL34 SE Mono Block design to be released at Newport!
I am posting here because interest was expressed in a higher power version of the Ambrose amp (10W).
We are putting this together as a pair of mono blocks:
Dimensions: 9"W x 17"L
Weight: < 50lb ea.
Tubes: (3)EL34's per channel + 1 driver tube.
Power: 30W+ per channel into 8 ohms.
The finish will be very similar to that of the Ambrose with black anodized top and bottom plates and front, back and sides from flamed maple. Price is projected to be $12K-$15K/pr.
If you are interested, please let us know! The show pair WILL be for sale and for a good price!
This is a production product, no longer just a concept piece.
Thanks,
Dan
-
Dan: This is GREAT news! Please post photos when you have them. What will you be pairing these with in Newport? Are you able to comment yet on how well these drive your Ulysses? Have you done any comparisons with the KWA150SE and your 845s?
-
I will sadly not be attending CAF this year. I had to forego CAF and Munich this year.
The 30W monos will be making their debut at THE SHOW in Irvine in June.
I am quite excited about this! I know how good the 10W Ambrose sounded with my Ulysses speakers and I have heard the 30W monos and they have the same magic, just A LOT more power and control! The 30W design will open the door to MANY more speakers!
I will post photos and listening impressions as the show units are built.
I am also toying with the idea of designing the ultimate PP Integrated amp in the 50W range. What is interest here? I have some ideas for a design will set it apart from the standard PP pentode amp sound...
Thanks,
Dan
-
For those who have followed our journey into tube amplifier design, I have a new potential offering!
Who would be interested in a 30W EL84 P-P integrated amp at a reasonable price? I am thinking of a very well engineered and beautiful sounding 30W integrated amp with four EL84's per channel. It will feature Electraprint proprietary and hand-wound output transformers, in a new design!
The build quality will be excellent, but not as exotic and expensive as the rest of our Ambrose amplifiers. The reason for this? Simply to keep the cost down and offer a GREAT tube integrated amp, that provides 30W of CLEAN, PURE, Tube power, at a price that most can afford.
Jack sent me a proof of concept for his new transformer design recently and I had a buyer for him within a few days. I can attest to the great sound he achieved with the new output transformers! I have ideas for an amp with a more sophisticated power supply and input stage and more power! the amp Jack sent was 10W and used two EL84's per channel. I am still waiting for Jack to prove that he can provide 30W output transformers but i believe it can be done.
Target price would be $3K-$4K - factory direct.
Thanks and I look forward to hearing from any who would be interested.
Dan
-
Dan ,
I am assuming it would be Push Pull mono amps. if they would be SET that would interest me :thumb:
Asghar
-
Dan ,
I am assuming it would be Push Pull mono amps. if they would be SET that would interest me :thumb:
Asghar
"P-P" in the model name indicates Push-Pull, and it's an integrated amp (not mono amps.)
-
What I am actually looking at is an EL84, Push-pull integrated amp. In order to get 30W or more, it has to be P-P. We have 30W EL34 SE mono blocks already, but they are more expensive.
I am looking for a cost-effective, stereo integrated, to provide 30W of clean and pure tube sound. The EL84 P-P design that I am thinking of, has the same beauty of sound as our A30 mono blocks! This is due to the use of virtually zero global feedback and unique output transformer design as well as phase splitting.
Thanks,
Dan
-
..... This is due to the use of virtually zero global feedback and unique output transformer design as well as phase splitting.
Thanks,
Dan
This is interesting. Normally, running el-84s with no (or very little) feedback causes the amplifier to have very high output impedance that does not sound good with most speakers. Are you doing something different to keep the output impedance low? What will it be?
My only critique of the design is the need for an octet of output tubes to get the 30 watts per channel. I do appreciate why you're looking for that power, however quality el-84s are quite expensive and an octet could cost $500-$1k.
I know my own habit is to listen at modest levels most of the time where the normal 15ish watts from a p-p el-84 amp runs would be fine. I've often wondered if there's any way a parallel p-p amp could be equipped to run as a p-p amp and then engage the second quad of output tubes when more power is wanted. Is that even possible?
-
The output transformers have a unique winding structure and are wound for 6 ohm impedance.
I understand that NOS EL84's are expensive, but in order to get over 20W, we would need four tubes per channel.
As to operating with two or four tubes per channel, the entire design of the output transformer is based on the impedance seen by the tubes. I.e. a very different impedance and bias setting for 2 tubes per channel vs. 4. This is why you never see units that can be made either way.
Dan
-
What about the hybrid tube integrated?
Gosh, Dan, all this new stuff, you have been a busy boy!
Joe
-
:(
Oh gosh, Dan, I didn't realize this thread seems to go back to 2016! I thought this was new for this year's RMAF.
Sorry.
-
Hi guys, there are two things here. The hybrid integrated amp has been in the works for some time and I am finally getting the rubber on the road.
I am starting with a KWI 200 as proof of concept, replacing the SS preamp circuit with a tube circuit. I then intend to re-design all the PCBs inside as well as the enclosure. There will be more exposed heat sinks for better ventilation and the output devices and circuit will be the same as the KWA 150SE, but probably 200W.
The tube integrated is a thought. I really liked what I heard from Jack Elliano's simple 10W P-P EL84 design. It sounded fresh, fast, dynamic and powerful. I have asked him to see if he can wind the transformers needed for a 30W+ amp, of course requiring eight EL84's total.
I could also do this with a pair of EL34's per channel, which I really like the sound of. I hesitate however, because everyone seems to get a bored look on their face when I mention the EL34 tube.
I also thought about a P-P 300B integrated, at about 25W.
If anyone has an opinion about the tube integrated design and tube choice, please let me know. I believe there is a market for a GOOD, reasonably priced, 25W-30W Class A tube integrated that sounds better than the current offerings on the market.
Thanks,
Dan
-
I would do it with 1625 tubes. It's what I did. It's a $10-20 NOS tube. They are 6L6 tubes with top caps. Made by the hundreds of thousands during WW2 for the Army Air Corps. I bought a box of 50 of them (I use 4 per channel with a pair of 6BL7s as my phase inverter and my driver tube). Sound is amazing. Just need to make sure to use plate caps that hold tight... It bested my 6BQ5 amp. Alternatively, you could add a switch to use 8bq5s or 10bq5s, which are the same tubes, but cheaper (I actually ran 10BQ5s at 6.6v and they sounded fine).
Shawn
-
How about a modern update on this one:
(https://www.audiocircle.com/image.php?id=184321)
-
I think EL84s are a very good sounding tube, and the new issue Gold Lions are only $45/pair, so you could retube the entire amp for less than $200.
How good are the GL's? Dunno - I have some Philips Miniwatt NOS EL84's here, I should do a tube shootout some day.
-
First of all, for liabilities sake, I will never use a tube with an anode cap. I realize there are many tubes that would be great to design with, but beyond my personal use, I am not willing to do it.
As for a two EL34 per side, P-P 30W-50W integrated, the technology used in the EL84 amp would apply and it could be FANTASTIC! Like I said though, when I mention EL34's, a lot of people yawn.
The EL84 is unique because it is not expensive (new stock), and it really produces a beautiful sound. Yes, it would take eight EL84's to produce the power I want, but I believe this has been a successful formula for Manley (Stingray) already.
I am targeting a $3K-$5K price range for this and it will likely be a factory direct business model. This will mean that we can offer a LOT more amp for the money!
In that price range, for 30W+ in a tube integrated, if you were/are in the market, what are you looking for?
Thanks,
Dan
-
I think an EL84 tube amp is a fantastic idea - it's a seriously overlooked tube and it sounds great. The world already has enough EL34/KT66/KT88/6550 amps.
Especially if you could arrange the quads of tubes in a cool pattern or otherwise give it some visual flair, it'd be a hit.
-
Thanks, I always like to make our gear look good! I was thinking of a dark grey to black powder coated enclosure with some texture perhaps with the transformer belends powder coated Illusion Malbec, which is a deep burgundy wine color. Silver or black knobs, not sure. Flat black if gloss chassis or gloss knobs if flat chassis. And yes, the tubes arranged in a visually pleasing way.
I am still waiting to hear how Jack makes out with the transformer design for four P-P parallel EL84's.
I appreciate your FB!
Dan
-
...... I hesitate however, because everyone seems to get a bored look on their face when I mention the EL34 tube.
I also thought about a P-P 300B integrated, at about 25W.
If anyone has an opinion about the tube integrated design and tube choice, please let me know. I believe there is a market for a GOOD, reasonably priced, 25W-30W Class A tube integrated that sounds better than the current offerings on the market.
Thanks,
Dan
I do understand why folks give you the blank stare when you mention the el-34 p-p amp. I feel like I've heard hundreds. Same for the p-p 6550 family. Many fine amplifiers in there, though.
I like the idea of the p-p 300b amp, except I'd have to get a quad of the new/reissued WE tubes. Unfortunately for me, if there are quality tubes available for my gear I use them, because they sound so much better. And it's also challenging to get both great bottom end and top end with the 300b.
One potential I'd like to see is a p-p 845 integrated. That would get you 50 watts per channel, and I'd find that more enticing than another 30 watt integrated. And NOS tubes are not realistically available to 99% of us. I wouldn't even consider it.
-
Thanks, I always like to make our gear look good! I was thinking of a dark grey to black powder coated enclosure with some texture perhaps with the transformer belends powder coated Illusion Malbec, which is a deep burgundy wine color. Silver or black knobs, not sure. Flat black if gloss chassis or gloss knobs if flat chassis. And yes, the tubes arranged in a visually pleasing way.
I am still waiting to hear how Jack makes out with the transformer design for four P-P parallel EL84's.
I appreciate your FB!
Dan
Plus the Gold Lion EL84 is a pretty nice looking tube (and sounds great too), and only $50 per matched pair:
(https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcT9-71mm3dfk__MXdolVzPsHNtfuBgxuVunuD9nu1k0ApBb8P3SRg)
-
Agreed, the EL84 is not expensive and can be readily sourced new at least, without breaking the bank.
In that same frame of reference, NOS EL34's, 300B's or 845's are going to cost a FORTUNE! I don't know that tube cost is really a relevant factor in this case. Or if so, then the EL84 is about the least costly of the bunch. The 300B and 845's new are among the most expensive. Even at four tubes total for 300B or 845, it would still be less costly to re-tube an 8-tube EL84 amp.
Now if the goal is to get closer to 50W, then the choices shift to 845, KT88, KT120, KT150.
Dan
-
The 845 P-P is another idea. The only drawback to using the 845 is the nominal/ideal 1200V operating voltage. Even 800V-1000V is still lethal and a bit unnerving to work with. The rest of the tubes we are discussing are operating in the 300V-500V range. That is a dangerous voltage, and it hurts when you slip up and get zapped, but it won't end your life.... We did one pair of 845 SE mono blocks and they were build to operate at 1200V. At that voltage, I had to take into consideration the wire insulation, proximity of any conductors with respect to anything carrying that voltage and even that all solder joints and connections had no sharp points or edges. At 1200V, a sharp point on a solder joint will cause a focused charge that will actually glow magenta as the air is ionized and turned to plasma.
We were able to achieve 32W with a single 845 in Class A2, pure SE. If we ran a pair on P-P Class A and ran the plates at closer to 800V, we could probably still comfortably get 40W-50W. I would have to see.
I LOVE the sound of SE 845's! The 845DS mono blocks that we built (90lb each!) are the most magical amps I have ever heard! They have a quality that is simply unique. We used a single gain stage (6HV5 tube - capable of 3KV plate voltage), cap coupled to an 845 tube transformer coupled as SET. The circuit is so simple and elegant!
I will consider this. I know that Line Magnetic has achieved success with amps in the $4K-$5K and similar power, using 845's. Being made in China is the only way that they can reach this price. I could probably come close, made in the U.S., factory direct, depending on the cost of the enclosure.
Thanks,
Dan
-
I agree that there is something magical about well implemented 845 amps. I'm sure your custom made monos are awesome.
Good luck with the el-84 integrated, and apologies for getting off topic.
-
Dan, have you ever considered doing Single Ended Parallel only and not do the Push-Pull? I've not heard one, but they are supposed to keep the magic of true SET sound while giving you more power.
-
We already have the A30 mono blocks, which use 3 x EL34 per channel in SE parallel to produce 30W of power. Because this is SE and pure Class A, the transformers are heavy, about 15lb each and as a result, the amps are mono blocks. Each amp weighs about 48lb with just two transformers and a single choke.
When it comes to SE power, 30W iron will be the same size, pretty much no matter what tube is used. P-P allows for smaller output transformers to achieve the same power. I also agree that most P-P amps that I have heard do NOT sound as good as just about any SE amp, whether SET or pentode tube. However, due to the unique winding configuration of Jack's output transformers - borrowing from technology perfected in development of the A30 mono blocks - the sound is still VERY sweet and musical. It does not have the cold, hard or even diffuse sound of most P-P amps.
In my opinion, it is the use of gross amounts of Global feedback in most P-P tube amps that causes this. First of all, much of the even order harmonic distortion is cancelled in P-P config, leaving only the odd order distortion harmonics. This is why a lot of global FB is used, to reduce distortion and also improve bandwidth. Jack has discovered that IMD - Intermodulation Distortion - plays a big role in the overall sound. By focusing on ways to reduce IMD, you already get much lower THD (Total Harmonic Distortion). So, even in P-P, while there are odd order distortion harmonics present, the overall distortion spectra is very low. And, most importantly, the IMD is very low!
I first heard this when visiting Jack several years ago to learn about transformer winding. At the time, I just wanted to be able to wind my own custom value chokes for different applications. Jack taught me a lot in that time. While I was there, I heard a 10W EL34, SE amp that he had designed, based on this low IMD technology. I was absolutely impressed by the sound of this little amp. I could describe it in no different way other than to say it was special and extremely musical. We compared it to a number of different P-P and even a 300B amp that he had built and none of them had the same qualities.
Our A30 amps are built with transformers that use the same winding technique as this first 10W amp. Jack used this same technology, applied to a P-P output transformer, and found that the same results with regard to IMD could be achieved there also. When he sent me the 10W EL84 amp to listen to, I heard that same magic as the 10W SE EL34 amp I heard several years ago.
So, to answer you question, parallel SE typically does sound better. The cost is paid in the size and expense of BIG output transformers. With Jack's new P-P transformers, I am confident I can achieve the same sound in a 30W integrated with transformers sized so as to NOT give you a hernia when you pick it up.
In closing, it is a fact, I have since learned, that given enough FB (skies the limit, right?!), the output transformers can be very small and have minimal core size. You could make a 100W P-P transformer, with enough FB in the design, such that the transformer's size would be MUCH smaller than a 10W SET output. It would measure well, with good BW and low distortion. It would sound terrible however and may also have no bass. Jack has taught me that there is a true art to the design of tube amp output transformers.
Dan
-
Ah gotcha. Thanks for the detailed response, that makes sense.
-
.........
-
Hi, this could certainly be done. Something like the EL84 design would not be a very large piece. In fact, the 10W unit could be quite compact. The problem is that 10W is a very limited market as far as speakers go. I would still think that the 30W version could suit your needs. What are the max dimensions that you would consider compact?
Thanks,
Dan
-
Another tube under consideration for a P-P tube integrated, is the 6L6. This tube has a long history in HiFi and there are A LOT of different 6L6 and variants available. Power ratings would support our goal of 30W I believe. Input welcome.
No matter what design we do, I don't intend for this to be a huge amplifier. It will really depend on the size and weight of the transformers, but P-P should allow us to keep this in check, in the 30W range.
Thanks,
Dan
-
Hi, this could certainly be done. Something like the EL84 design would not be a very large piece. In fact, the 10W unit could be quite compact. The problem is that 10W is a very limited market as far as speakers go. I would still think that the 30W version could suit your needs. What are the max dimensions that you would consider compact?
Thanks,
Dan
Hi Dan.... I was thinking about a good tube preamp. Not looking for an amp. Something small with true balanced circuits.
-
Another tube under consideration for a P-P tube integrated, is the 6L6. This tube has a long history in HiFi and there are A LOT of different 6L6 and variants available. Power ratings would support our goal of 30W I believe. Input welcome.
No matter what design we do, I don't intend for this to be a huge amplifier. It will really depend on the size and weight of the transformers, but P-P should allow us to keep this in check, in the 30W range.
Thanks,
Dan
Of all the pentodes, the 6L6 might be the closest in sound to a true SET. I have a pair of RCA 6L6GA tubes in my amp right now and they are just beautiful sounding.
-
Thank you, that may be a way to go! I just need to see if we can achieve 25W-30W in an integrated with these tubes.
Dan