29-MAR-2025
OT19PP-DYN35-USA Our Dynaco 35W product (OT19PP-DYN35-USA) is doing well with customers.  We've added a Specification and Option document to help explain the various cover options for ZInc/Chrome/Black and Shallow OEM style mounts for the original ST35 and SCA35 chassis style

Added updated specifications for OT12SE-HF-XX, OT15SE-HF-XX and OT20SE-HF-XX HiFi parts.  These are all EI 1IN bobbin/lamination sized windings with (3) different lam stack heights and Gap papers adjusted for 12W/15W/20W outputs. 

We have a direct source now for Z11 lams that has been approved & by mid-May we should have steady supplies of this lam for Dynaco and Single-ended HiFi use.  Z11 in M6 (14mil thickness) is running about 15% higher than 29M6 lams in permeability.  So for the same core size we expect about a 5Hz improvement in low end response.

Having trouble getting schedules and commitments out of Mexico for the regular EBay products we build to our own designs.  OT5PP, OT8SE, OT12PP and soon OT10SE need restocking.  Working on backup plans.

So far tariffs have not been a factor in MPS costs.  For now US Customs is still not staffed to assess entries under $800 declared value.  We're Trying to keep any imported components under that level to hold costs.  I imagine our Amazon stock prices will drop thru the floor if US changes this rule. 

Most Bobbins, Silicone Steel and Copper for transformers originate offshore...... 
Transformers or windings built in Mexico under USMCA agreement like our MX transformer seem to be about to get whacked.....  stayed tuned.   This could get tricky.

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27-Sept-2024

Headed into the Fall with a nice backlog of custom projects:
>Mostly seeing SE + PP HiFi OT's in 2K5 and 5K version requests, but some interesting Guitar requests (Drake 784-139 type build). 
>The OT5SE was created for a a Vox AC4 replacement and seems to have landed steadily in a Morgan offering.  I may keep that one on the shelf
>Ordered up a bunch of transformer cover options .  I have Chrome and Black Bells for my PTXXX.2 (EI-1IN) and PTXXXMi (EI 1-1/8IN) sizes and larger OT's on those two lam sizes
>I have the shallow EI-1IN covers for the Dynaco ST35 in Black and Chrome, using a black bracket for the mount.
>We're carrying Lams and Covers now for the larger EI1-1/4 size & we've got a range of OT and PT bobbins in stock now for large custom PT and OT work.
>We can do custom laydown PT project now in EI-1, EI-1-1/8 and EI-1-1/4 now.  Just ask.

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21-JULY-2024

OK- there is a pricelist update.  The main driver for any increases being price changes on the MX made guitar OT parts & increased inbound freight costs from UPS.  Steel for Laminations has doubled in price.  Copper magnet wire too.  I can get imported iron in the same audio grades but in low volume air-freighting it into the US works out about the same.

M-Series Power Transformers
PT winding assemblies were received for the (5) "M" sized power transformers.  Assembled, these all worked correctly to specification. 

The supplier did manage to put all the input and output windings on 1 side of the coil assembly, so the (4) samples I had available after approvals were built into LAYDOWN versions see here-  https://www.instagram.com/p/C72Wmldyrae/

The winding assemblies ordered were received and a couple of each have been completed & tested and are now in stock.  The PRODUCT page has a PDF drawing for "M-Series" 85VA Power Xfmrs now.  These will be gernerally provided in upright FM200 endbells.  

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MARCH update-

I've been catching business from Shop (morgancustomshop.com) the Morgan Amp local HQ.  Joe picked up my small PT190.1 and the OT5PP and OT8SE early last year and has restarted his low power "5" amps.  He's been using the PT285M, OT12PP and OT20PP on his custom projects & he's trying out the OT45PP-JTM/OT50PP-JCM.  Must be doing something right here.  Check out the 5W AC5 here- it's running an OT8SE OT and my smallest PT190.1 power xfmr:  https://www.instagram.com/reel/C9lH9R-u-_T/?utm_source=ig_web_copy_link&igsh=MzRlODBiNWFlZA==

The OT15SE-HF-5K-UL  got tested recently by SKUNKIE DESIGNS Skunkie Designs | Tube Audio Electronics .  Stef ordered more sets and found a lower distortion on the MPS part than what was being seen in the competitive part.  I believe this is the 300B project.. but I have not been thru all of the YouTubes out there to find the specifics.  I'm building a pair now with Z11 lams which allows for a tighter wind with fewer turns than 29M6.  On the bench the Bass response isequivalent and the Leakage Inductance losses are down a third.  On paper... that's all good.

OT19PP-DYN35 update- I've got a couple of pairs done using the current recipe.  They test out at full pretty solidily 24Hz to 40KHz at 17.5W+.  About 15W at 20Hz.  I've decided to run with this version for now using Z11 laminations to make up for the relatively low permeability I saw in 20 versions of current 29M6 in testing with Dave Gillespie.  Like all things in classic audio there's certainly a bit of lost art and perhaps magnetics supply chain decline at work here.  

So a pretty good mix of Guitar Amp and HiFi activity going on now hee in Columbia TN!!!

HiFi OT's in EI-1 INCH & EI 1-1/8INCH sizesChrome Covers available now

Other recent New Stuff 

Working on several HiFi projects & now have an assortment of better looking covers for HiFi projects including painted and a polished plated version.