CP 04-006s

CP 04-006+ in process. 10 madc at 175 H VLC (very low capacitance) twin coil construction mirror imaged noise canceling nom dcr of 425 ohms

CP 04-006 In process two units in brass channels

MQ Dowdy Choke

NOS Valves' VRD Amplifier with MagneQuest iron!

Craig Ostby at NOS Valves dropped us a line to let us know he used some of our transformers in a VRD Amplifier he built for a customer and they were over the moon with the quality sound!

Craig himself said, "The HF response was so much better I could cut the feedback smoothing cap value in half without any nastiness with square wave performance. This is saying allot since the stock transformer is no slouch! More importantly to my ears this was a really nice improvement across the board."

After a couple days of listening, his customer had the following to say to Craig, who kindly shared with us! "The amps are like a religious experience man. Clear, clean, and flowing music. From top to bottom, sound is more even handed, more dimensional, and just plain sounds good. The stock transformers were somewhat rougher sounding and a bit tipped up or hot in the presence regions. I didn't really notice that until I heard these! Such important musical improvements these make. I am hearing the most realistic displays of depth I have ever heard out of 2 speakers. Absolutely fantastic. You done good, no doubt about it. Tell Mr. MagneQuest his transformers are fukin musical instruments."

Check out his setup:

BCP-15 + plate chokes.

These are a special version of our standard BCP-15's. 

Same electrical specs. It's a plate choke optimized for the 45 tube. Standardly airgapped for 40 mils of plate current. It has 50 henries of inductance and 525 (nominal) ohms of winding resistance. 

An alternate airgap can be used which yields 40 henries at 50 mils of plate current. This arrangement can be used with 2A3 tube operating at 300 volts on the plate, -45 grid volts, and 50 mils of plate current.

What makes these special is that the plus model depicted in the photo incorporates key elements of our new proprietary inductor designs as highlighted in a post earlier this month.

It has mirror-imaged twin coils in a series-aiding noise cancelling (humbucking) arrangement. It is stacked with premium M3 laminations (.009" thick) which have exceptionally low core losses. Comes in solid brass channel frames. All solder connections are made with a silver bearing alloy.

Available in limited quantities for a limited period of time. These are the best BCP-15's hat I have made. 

$250 a pair plus shipping. Email me at acrosound@aol.com to order.

Introduction of a UHP series of inductors/transformers

Hello Folks,

I'm really happy to announce a premium series of mirror-imaged twin coil, noise cancelling, and symmetric low capacitance designs. These will be available as an option in many of our plate chokes, grid chokes, input transformers, etc.

These ultra high performance designs have been carefully engineered and evaluated over a lengthy development time-frame. We have gained enough experience in building these to be able to offer them as enhancements to our already heralded audio inductors and transformers. These are much more labor intensive to build and hence the pricing will reflect the increased costs.

These UHP designs are strictly proprietary, and are exclusive to MagneQuest. I will not provide in-depth technical treatises on our proprietary developments. Where possible I will endeavor to spell out what the performance advantages are in specific applications.

Many of the major concepts incorporated into this new series have been demonstrated in prior OEM work that we've done for Wavelength Audio as well as some of the craft techniques developed for use in our very special Mexico series B7 input transformers. We recently built some OEM power supply filter chokes for Serious Audio (to their electrical specs) that embody several of the key concepts described above.

Our first offerings will be for our B7 10K:10k input transformers. All electrical specs such as impedances and power levels remain as previously published.

We have some top shelf Penny & Giles RF-15 potentiometers avaiable for purchasers of our input transformer listed above.

Next up will be some of our plate chokes\grid chokes.

MSL

A New Attenuator

there's a new attenuator available. Read DHTRob's impressions below.

the unit reviewed was a 100K ohms... and I actually have some inductor loading options for this high value...

but in all likelihood Amtrans can probably make a 10K version in which case you can use our B7 10K:10K input trans with the 10K attenuator across the secondary.

Also... here's a sneak preview... I will soon be announcing a new series of "mirror-imaged, twin coil, hum-bucking, and symmetric low C" designs.... which will be available as an option in many of our plate chokes, grid chokes, input transformers, etc....

http://www.dhtrob.com/impressies/amtrans_sats.php

We love to hear from you

Questions, comments, and order inquiries can be communicated to us via several different  SMS, chat, and messenger apps.

Via KIK:

Download Kik by going to m.kik.com on your phone (it's free and crazy fast). My Kik username is "mqracing" - add me!


Via Whatsapp: please contact me first by email

Via BBM: please contact me first by email 

Via Facebook: please contact me first by email 

My email is acrosound@aol.com 

DIY Plans: HTS-5504-1

Hello folks:

We've had a lot of inquiries on the MQR-5504 power transformer which was used in the Baby O and Bugle circuits designed by Gordon Rankin of Wavelength Audio fame.

Since we are a really small (nano sized :=) winding house and are frequently booked pretty solid--- we aren't able to accomadate building this power transformer in-house any longer. It's just not efficient for us to produce these.

Enter Heyboer transformers. I contacted them and asked if they would have an interest in building these for our customers. I've supplied them with the original blueprints so that they could make an electrical equivalent. 

The new part # for units sourced through Heyboer is HTS-5504-1. You can and must order direct from Heyboer. Units produced by Heyboer will be covered by their warranty if any.

They will have a spec sheet available for this part number.

Pricing as relayed to me will be $130 for singles and $110 each if ordered in pairs.

ALL questions and queries should be directed to Heyboer. 

phone: 616-842-5830 or email at phil@heyboertransformers.com

MSL

TL-404

10 khz square wave

TL-404 frequency response

TL-404

MagneQuest works best with the following tubes.

Custom-Built MQ-565s on Sale

****FOR LIMITED TIME, CUSTOM-BUILT MQ-565s!****

We have SOLD OUT pairs of M6 nickel pinstripe MQ-565s in stock. These come in black oxide steel covers, but could be switched into brass bell ends for an additional fee.

These babies have a primary impedance of 7100 ohms CT with UL taps, and a secondary impedance of 8 & 16 ohms, MOL 17.5 watts.

Nickel lams are increasingly harder to find at any price, and these puppies are not a regularly stocked item, so snatch up these nickel pinstripe MQ-565s before they're GONE!

$400 per pair M6 nickel pinstripe

We'll accept payment via PAYPAL (you pay shipping) or by U.S. POSTAL MONEY ORDER (in which case, shipping is on us).

Email acrosound@aol.com if you have any questions or would like to place an order.

Peerless catalog of 20-20 Series output transformers

 

Click on the photo above to enlarge.

Gordon Rankin of Wavelength Audio scores a "best of show" in coverage
by The Audio Beat ezine. 

http://www.theaudiobeat.com/rmaf2013/rmaf2013_wavelength_vaughn.htm

1960 Freed Transformer catalog

http://tinyurl.com/ncyquw8

or
http://ebookbrowsee.net/freed-transformer-company-1960-rem-24-pdf-d438795004

Glamour Shot: EXO-046s

This EXO-046 is one of a pair. Built with nickel lams and housed in steel channel frames, they're sleek and sexy.

Primary impedance 5000 ohms. Secondary impedance 16 ohms.  MOL 2++ watts.  Parafeed. Most often used with the 45 tube and a  BCP-15 plate choke. Great for use with 16 ohm single full range drivers.

Want to own a pair? Email us at acrosound [at] aol [dot] com.

Glamour Shot: FS-030

This FS-030 is one of a pair built with special covers. We love the contrast of the pale green with the black painted lams. Don't you?

For complete specs www.magnequest.com/FS030.htm

Interested in owning your own pair? Email us at acrosound [at] aol [dot] com.

Build and Let Build

"C'mon, this is a hobby -- you enjoy it your way, and I'll enjoy it mine, and if aesthetics and industrial design happen to be important to me, who cares? Listen and let listen. Build and let build."

So wrote member Jim R. of the Bottlehead forum on a post a while ago about polishing brass bell ends. While transformers and DIY audio are our business, we hope our customers enjoy themselves when using our products.

And he brings up an interesting question: What's important to you in audio transformer design? (Speaking of aesthetics, don't you love the above picture of our MQ-470?)

From the Bottlehead Forum: About the BCP-15

The BCP-15 was an original Freed design.  It was originally spec'd at 50 madc and 40 Henries. We built many of these to the original specs. These would tend to have only the BCP-15 marked on them.  

Later... realizing that most people who were purchasing these plate chokes were using them with the type 45 tube which runs moreso typically at 35 to 40 mils of plate current. After careful analysis of the original design we were able to regap the unit and optimize it for use with the 45 tube at the ballpark 40 mils instead of 50 mils of plate current. With the smaller airgap, we picked up more L (50 henries).

Once we offered the second choice -- 40 mils at 50 henries or 50 mils at 40 henries -- I've tried to be consistent (bearing in mind the existence of human frailty) and mark the coils that were gapped for 40 mils. Often times (but not always) this demarcation might be written on the back side of the coil.  

The 50 mil coils may or may not have the marking -- if it's not marked--- again allowing for the occasional human error -- it is most likely gapped for 50 mils. 

This description comes from the Bottlehead forum for "All things MagneQuest." Check out the thread here.

Have You Met Our Robin Hood Series?

The Robin Hoods' series consists of three single-ended air-gapped output transformers. The aim of the series is two- fold. First is to offer a transformer for folks who are bi-amping and don't need the huge inductances and AC power capabilities of say our legendary FS-030 single ended  output transformer.

The second aim/goal is to make these the best VALUE output transformers available in the marketplace. The "Robin Hood" series is named in honor of the man who took from the rich, as in the richness of MagneQuest's proven designs, to give to the poor, as in DIY lovers who crave high value without sacrificing top quality.

The primary copper circuit is smartly crafted to keep resistive losses at a minimum (the dcr is approx. 185 ohms). The copper losses from the full secondary and the full primary are equal in magnitude. The primary inductance is carefully designed to fully support the published low frequency extension of each model at the maximum stated power level. The total (AC and DC combined) magnetic flux density is kept BELOW 16kg in each model offered in this series. Therefore, these will not saturate or "run out of iron" when used within their published specs.

Simply put, these are expertly designed transformers with an emphasis on sound quality. We didn't skimp in the goodies department. All of the RH series are made with pure Teflon insulation on the inside. All solder connections are made with silver bearing solders. All units are housed in channel frames with easy to solder to terminals. They are as easy to install as they are musical in their sound delivery.

Currently, three different models are available in the following configurations. All have 5K primary impedances.

Here are the specs for the RH-40, RH-60, and RH-80 which cost $125 each.