New Directions at Modwright!!!

modwright · « **Reply #20 on:** 25 Feb 2016, 10:12 pm »

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

dodgealum · « **Reply #21 on:** 26 Feb 2016, 08:07 pm »

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.

modwright · « **Reply #22 on:** 3 Mar 2016, 11:01 pm »

We have the design worked out. It is just a matter of demand.

Thanks,

Dan

beaglebump · « **Reply #23 on:** 3 Mar 2016, 11:23 pm »

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.

modwright · « **Reply #24 on:** 21 Apr 2016, 11:47 pm »

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

dodgealum · « **Reply #25 on:** 26 Apr 2016, 12:19 pm »

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?

modwright · « **Reply #26 on:** 26 Apr 2016, 02:29 pm »

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

modwright · « **Reply #27 on:** 9 Sep 2018, 05:18 pm »

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

A_shah · « **Reply #28 on:** 10 Sep 2018, 07:06 am »

Dan ,
I am assuming it would be Push Pull mono amps. if they would be SET that would interest me

Asghar

audio.bill · « **Reply #29 on:** 10 Sep 2018, 11:55 am »

Quote from: A_shah on 10 Sep 2018, 07:06 am

Dan ,
I am assuming it would be Push Pull mono amps. if they would be SET that would interest me

Asghar

"P-P" in the model name indicates Push-Pull, and it's an integrated amp (not mono amps.)

modwright · « **Reply #30 on:** 10 Sep 2018, 01:46 pm »

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

Rusty Jefferson · « **Reply #31 on:** 11 Sep 2018, 01:26 am »

Quote from: modwright on 10 Sep 2018, 01:46 pm

..... 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?

modwright · « **Reply #32 on:** 11 Sep 2018, 01:52 pm »

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

Joe Frances · « **Reply #33 on:** 11 Sep 2018, 06:04 pm »

What about the hybrid tube integrated?

Gosh, Dan, all this new stuff, you have been a busy boy!

Joe

Joe Frances · « **Reply #34 on:** 11 Sep 2018, 06:07 pm »

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.

modwright · « **Reply #35 on:** 11 Sep 2018, 06:59 pm »

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

sfox7076 · « **Reply #36 on:** 11 Sep 2018, 07:06 pm »

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

jhm731 · « **Reply #37 on:** 11 Sep 2018, 07:06 pm »

How about a modern update on this one:

Tyson · « **Reply #38 on:** 11 Sep 2018, 07:09 pm »

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.

modwright · « **Reply #39 on:** 11 Sep 2018, 07:14 pm »

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