Transformers for 18 watt

[ab3640au]

I know there's been lots said about transformers and being a "newbie" I've spent some time reading through lots of posts. In Australia (like the UK), we have 240 volt mains. Also, power and output trannys are a little harder to come by here. I can get Hammond trannys - for PT the 370BX or 370FX has been suggested by a supplier, while for OT either a 1608 or 1609. I'm getting to the point now where I'm starting to acquire my parts and want to be sure that I get it right. I'm curious about the Heyboer tranny's (particularly OT), but have no idea how I would source these from Australia. Are they really that much better than the Hammond (and if so why - in your opinion?). From my perspective, I want to do this right - hence the "newbie" questions.

[GlennG]

Hello and welcome to the group. The Heyboers are good transformers, I use them exclusively. Hammonds are good also but the reason the Heyboers are so popular here is because they were designed after the original Radio Spares that Marshall used in the real 18 Watt Marshall amps. Another reason they are popular is that it has the required , extra 6.3vac tap for the ez81 rectifier. And the price is not to steep. You can purchase the Heyboers from well of course, Heyboer and Graydon Stuckey . Shipping might be a little costly but will be worth it when your playing your amp months from now.

Glenn Gertis

[Graydon]

Hi,

Everything Glenn said is right-on except that you can't buy the 18W trannys from Heyboer. GDS Amps is the only source on those and although I am out of stock right now, I expect a new shipment in a week or two.

I have shipped to Australia before. It costs around $75. The Heyboer 18W PT has a 240VAC tap. I even have some special ones with a 100VAC tap in case we have any Japanese customers.

Contact me off list for details.

[zaphod_phil]

I'm curious about the Heyboer tranny's (particularly OT), but have no idea how I would source these from Australia. Are they really that much better than the Hammond (and if so why - in your opinion?).

Here's a posting from the old 18W site, by Ross Hughes - it looks like Hammond's 125E is recommended over their 16XX, but the Heyboers turn out to be the best!

-------------------------------------------------------
From: "rossh777 <rhughes@f...>" <rhughes@f...>
Date: Thu Feb 20, 2003 2:59 pm
Subject: OT Transformer Observations

I've tried 4 different OT's on my 18 watt and wanted to give some
input on them. None of them were bad...but they were all different.
They were:

1. 1650F Hammond 25w - I first tried the 1650 because that is what I
had. It sounded fine but I couldn't get much breakup. It had fine
low end and if I could have pumped 20 more watts in to it I might
have appreciated it more.

2. 1608 Hammond 10w - Then I bought this 1608 because it had a nice
price, lower wattage, and I heard good things about it on this site.
Very nice improvement! Much better breakup than its big brother.
More sustaining and more of an...almost...compressed tone. I thought
this was it. I didn't lose the low end either.

3. 125E Hammond 15w - Then I tried the old faithful 125E. I think
this fits even better. This is a great small amp tranny. This style
seems more tube amp based that those hi-fi 1600 series OT's. The
125E seems to break up even more and just gives it a bit more of that
good ol' tube amp sound...on the dirt side that is. This lost a
little more low end but not enough to fret over. I prefer this over
the 1608 to get that 18 watt Marshall tone.

4. Heyboer (from Graydon) - Put simply...this thing rocks! I am so
glad I bought this thing (thank you Graydon). I don't know exactly
what the difference is but there is a bit more breakup than all of
them. It looks like a heavy duty 125E. It has that edgy, punchy,
full of sustain sound. It was a significant tonal change. It is
just what I was looking for. I should have started here.

I know there are people who are satisfied with the 1608 and the 125E
(and they do sound good) but don't rule out these Radio Spares
clones. If I was going to start over and build one from scratch I
would skip to the end and just get the Heyboer. I'm assuming the
EMC's are the same but I haven't tried one.

Just some opinions,

Thanks for all of the help,
Ross

[ab3640au]

Thanks Guys ... I'll follow up off-line with Graydon re the Heyboers. I'm in no rush with this project ... I haven't got all the cash right now anyway, so I'll gradually acquire all the parts, do some research and reading (via this site and "Valve Amplifiers by Morgan Jones"). I know I'll make mistakes, just like everyone else, however your guys have "been there before" and I might as well learn as much as I can as from those who have done it ...

Barry Marie

[Attilio]

Hi all!
I found a guy here in Italy that sells very cheap PT...
He has 250+250@100mA-6,3@4A 140VA.
I think it would be ok for a solid state rectified 18watt lite II. Are 100mA enough for this purpose?
Thanks!
Bye!

[fixer]

i've heard emc tranformers are good dose anyone know how to contact them.

[Plexi]

EMC.. info..Contact John Cerniak at EMC at 972-272-3033 after 4 p.m. US central time (GMT-6) to order.
Thats the last info i had on them..

You may have to wait a while to get the EMC.. They are rated 300-300
the Heyboer are 290-290

So you'll have a wee bit more voltage using the EMC.

As for Attilio's question.. that may be a little on the weak side..
But may work depending on how they are built. I've used a PT close to that rating and it seemed to do ok.. Just lower voltages.


And to respond to Ross, that was very informative info.. trying all those transformers. It also shows that the OT plays a big part in your tone and sound. now you know why people look for certian transformers..for there amps:)

I also like the Heyboers, all the transformers i have got from them have been well built.

Richie

[zaphod_phil]

As for Attilio's question.. that may be a little on the weak side..
But may work depending on how they are built. I've used a PT close to that rating and it seemed to do ok.. Just lower voltages.

If Attilio uses solid state rectification as he suggests, he'll get a good 25 watts of 350V DC out.. Might be a good idea then to use Paul Ruby's trick of putting .01uF caps across each rectified to get rid of higher frequency 'hash' getting into the amp.

[Attilio]

Thanks guys!
My next project is to convert my normal channel to EF86 and maybe mod the PI in Jason style.
I think I will use that PT for my next dual EL84 build.

Thanks again!

Bye!