NAD :: 1969 Ace Tone 601 50w Tube Head

Udonitron · 01-29-2011, 03:01 PM

Figured I would put pics up since Ryan was asking to see the schematic and additional shots and perhpas all you other amp guru's can chime in as well?

I am planning to rewire the head for 5881's or 6L6GB D's so I have a little less clean headroom the stock 7591's offer.
Anyone familiar with rewiring a 7591 to a 5881 or 6L6 (essentially the same tube minus a few watts and less headroom)

I will have to replace the caps etc and I was going to rewire it but it seems to be OK for the most part via the wiring after inspection.
Not sure what the "Tuning" knob is for, it has an off position and then acts like a volume etc pot but needs replacing at it just continually spins.

Photos are dirty but I just cleaned the entire chassis and board with Simple Green, light misted water, followed by circuit board cleaner.
Looks a lot better...it was filthy!
Won't be plugging it in for a while so no worries

Ryan, here are a few shots for you man.

SLIDESHOW:

1969 Ace Tone Model 601 50w Tube Head

tonebone · 01-29-2011, 04:03 PM

7591.

Isn't that the tube that's legendary with tele's?

Udonitron · 01-29-2011, 04:27 PM

It is a VERY clean sounding tube with loads of clean headroom
I am sure it would sound nice with a Tele

Cygnus X1 · 01-29-2011, 05:56 PM

Ampeg Jet and a few others used 7591's.
Also good for Hi fi use.

I'd have to check but I think the primary Z (output transformer input impedance) is a closer match for 6V6's.
Rewiring the sockets will be necessary, not to mention bias supply tweaks if not more.
Before I saw the faceplate I said..,"Japanese", without thinking.
I wouldn't be surprised if there was a Univox relationship.

If it were mine I would replace those bulging filter caps, keep the 7591's, and run it for a while like that.

Looks like a very cool amp!

Udonitron · 01-29-2011, 06:53 PM

Cool, thanks for the info man.
Yeah caps are going 100%
Any preference for caps?

Yeah I am pretty sure it is a 69 so just before Roland took over.
Roland bought out Ace Tone in 1971 and the EC-10 Echo was in reality Roland's 1st tape echo unit.
Ace Tone Ended in 1972 when it became solely Roland
They made amazing gear...their fuzz pedals are amazing

wulfman · 01-29-2011, 06:55 PM

Hi Chris,

I hope I can piggyback on your thread here a bit since I got the same amp with a cab after you posted info about it, and unfortunately mine needs a fair bit of work too.

Mine has all the tubes but definitely is not in working order. The anodes on the tubes get red-hot when standby is off and the only sound I can get out it now is a faint volume when the tremolo and channel 1 pots are around 2 o'clock.
I guess I will need to sort the tubes out first. I have read that there could be a few causes, either tubes or tube sockets so perhaps I will get some new tubes just to see. They are hard to come by I guess but there is a 7591 Sovtek that seems affordable.

The cab, on the other hand, was worth the price of admission. I have the baffle off now but it is closed back, and looks like 2 12" Alnico speakers. I have been using it with my Egnater Tweaker head and like it a lot more than the Egnater Celestion cab. Much more rounded mids and highs.

Cheers,

Wulfman

Cygnus X1 · 01-29-2011, 07:21 PM

By the accounts I have seen all over the builder's forums the new issue 7591's are good, apparently very good.
The vintage 7591 tubes were going literally insane in price before the new ones came out.
There were all sorts of stories, including the one detailed on Geofx about one man buying nearly every one available through various sources to keep in Japan, or in his stash.
Here's the quote, true or not:
Cautionary Tubes - these are very hard to find

- 7591/7591A - legend has it that these otherwise excellent tubes were all bought up by an oriental buyer who toured the USA paying cash for all of them he could find, then disappearing. You are likely to only find used ones or the odd pair in some out of the way place. Dealers will in general not have them. I have personally seen trays full of NOS 7591A's for sale in the Akihabra electronics district in Tokyo, lending some credence to the rumor.

Brought the prices right back in line when the new ones came out.

Udonitron · 01-29-2011, 07:42 PM

NP Wulf!
Welcome aboard

Yeah I read that Cygnus
Interesting but I am happy they re-released them
You can get a matching set of JJ's for about $40 shipped.

Udonitron · 01-29-2011, 10:28 PM

Hey Cygnus

So the caps in that are 2 x 250v 100uf & 2 x 350v 20uf (more $$ for those)
Do you suggest I replace them underneath with these and leave the stock caps there for originality?
Cheers

3 NOS Sprague ATOM Capacitor Electrolytic 250V 100uf on eBay.ca (item 120677140735 end time 01-Feb-11 15:12:31 EST)

New 1 pc. 20uF 350V Axial Electrolytic Capacitor 20mfd on eBay.ca (item 130479617121 end time 25-Feb-11 10:10:38 EST)

ryan7olson7 · 02-01-2011, 03:51 PM

Quote:

Originally Posted by Udonitron

Hey Cygnus

So the caps in that are 2 x 250v 100uf & 2 x 350v 20uf (more $$ for those)
Do you suggest I replace them underneath with these and leave the stock caps there for originality?
Cheers

3 NOS Sprague ATOM Capacitor Electrolytic 250V 100uf on eBay.ca (item 120677140735 end time 01-Feb-11 15:12:31 EST)

New 1 pc. 20uF 350V Axial Electrolytic Capacitor 20mfd on eBay.ca (item 130479617121 end time 25-Feb-11 10:10:38 EST)

thats what i would do, it's gonna be big bucks to replace those cans.

ryan7olson7 · 02-01-2011, 03:52 PM

Quote:

Originally Posted by Udonitron

Hey Cygnus

So the caps in that are 2 x 250v 100uf & 2 x 350v 20uf (more $$ for those)
Do you suggest I replace them underneath with these and leave the stock caps there for originality?
Cheers

3 NOS Sprague ATOM Capacitor Electrolytic 250V 100uf on eBay.ca (item 120677140735 end time 01-Feb-11 15:12:31 EST)

New 1 pc. 20uF 350V Axial Electrolytic Capacitor 20mfd on eBay.ca (item 130479617121 end time 25-Feb-11 10:10:38 EST)

thats what i would do, it's gonna be big bucks to replace those cans. but you can get smaller ones than atoms, use the regular sprauge caps, they are the same thing just smaller. the atoms are hust more money for a bigger case.

Udonitron · 02-01-2011, 03:56 PM

The current cap cans are not budged at all however but no clue on the condition and the amp has not been plugged in while I have owned it so they are all nice and discharged.
Good time to replace em

01-29-2011, 03:01 PM	#1 (permalink)
Udonitron Oh Great...99 Yen!? Join Date: Aug 2009 Location: On an Island in BC Posts: 11,167 Thanks: 25 Thanked 56 Times in 23 Posts	NAD :: 1969 Ace Tone 601 50w Tube Head Figured I would put pics up since Ryan was asking to see the schematic and additional shots and perhpas all you other amp guru's can chime in as well? I am planning to rewire the head for 5881's or 6L6GB D's so I have a little less clean headroom the stock 7591's offer. Anyone familiar with rewiring a 7591 to a 5881 or 6L6 (essentially the same tube minus a few watts and less headroom) I will have to replace the caps etc and I was going to rewire it but it seems to be OK for the most part via the wiring after inspection. Not sure what the "Tuning" knob is for, it has an off position and then acts like a volume etc pot but needs replacing at it just continually spins. Photos are dirty but I just cleaned the entire chassis and board with Simple Green, light misted water, followed by circuit board cleaner. Looks a lot better...it was filthy! Won't be plugging it in for a while so no worries Ryan, here are a few shots for you man. SLIDESHOW: 1969 Ace Tone Model 601 50w Tube Head __________________ Tales From The Woodheap Flickr

01-29-2011, 04:03 PM	#2 (permalink)
tonebone Senior Member Join Date: Feb 2008 Location: West Coast Posts: 5,268 Thanks: 77 Thanked 81 Times in 17 Posts	Re: NAD :: 1969 Ace Tone 601 50w Tube Head 7591. Isn't that the tube that's legendary with tele's?

01-29-2011, 04:27 PM	#3 (permalink)
Udonitron Oh Great...99 Yen!? Join Date: Aug 2009 Location: On an Island in BC Posts: 11,167 Thanks: 25 Thanked 56 Times in 23 Posts	Re: NAD :: 1969 Ace Tone 601 50w Tube Head It is a VERY clean sounding tube with loads of clean headroom I am sure it would sound nice with a Tele __________________ Tales From The Woodheap Flickr

01-29-2011, 05:56 PM	#4 (permalink)
Cygnus X1 Senior Member Join Date: Jul 2009 Location: South Carolina Posts: 5,872 Thanks: 110 Thanked 101 Times in 32 Posts	Re: NAD :: 1969 Ace Tone 601 50w Tube Head Ampeg Jet and a few others used 7591's. Also good for Hi fi use. I'd have to check but I think the primary Z (output transformer input impedance) is a closer match for 6V6's. Rewiring the sockets will be necessary, not to mention bias supply tweaks if not more. Before I saw the faceplate I said..,"Japanese", without thinking. I wouldn't be surprised if there was a Univox relationship. If it were mine I would replace those bulging filter caps, keep the 7591's, and run it for a while like that. Looks like a very cool amp!

01-29-2011, 06:53 PM	#5 (permalink)
Udonitron Oh Great...99 Yen!? Join Date: Aug 2009 Location: On an Island in BC Posts: 11,167 Thanks: 25 Thanked 56 Times in 23 Posts	Re: NAD :: 1969 Ace Tone 601 50w Tube Head Cool, thanks for the info man. Yeah caps are going 100% Any preference for caps? Yeah I am pretty sure it is a 69 so just before Roland took over. Roland bought out Ace Tone in 1971 and the EC-10 Echo was in reality Roland's 1st tape echo unit. Ace Tone Ended in 1972 when it became solely Roland They made amazing gear...their fuzz pedals are amazing __________________ Tales From The Woodheap Flickr

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01-29-2011, 06:55 PM	#6 (permalink)
wulfman I'm calling dibs! Join Date: Apr 2010 Location: Singapore Posts: 4,779 Thanks: 15 Thanked 50 Times in 19 Posts	Re: NAD :: 1969 Ace Tone 601 50w Tube Head Hi Chris, I hope I can piggyback on your thread here a bit since I got the same amp with a cab after you posted info about it, and unfortunately mine needs a fair bit of work too. Mine has all the tubes but definitely is not in working order. The anodes on the tubes get red-hot when standby is off and the only sound I can get out it now is a faint volume when the tremolo and channel 1 pots are around 2 o'clock. I guess I will need to sort the tubes out first. I have read that there could be a few causes, either tubes or tube sockets so perhaps I will get some new tubes just to see. They are hard to come by I guess but there is a 7591 Sovtek that seems affordable. The cab, on the other hand, was worth the price of admission. I have the baffle off now but it is closed back, and looks like 2 12" Alnico speakers. I have been using it with my Egnater Tweaker head and like it a lot more than the Egnater Celestion cab. Much more rounded mids and highs. Cheers, Wulfman __________________

01-29-2011, 07:21 PM	#7 (permalink)
Cygnus X1 Senior Member Join Date: Jul 2009 Location: South Carolina Posts: 5,872 Thanks: 110 Thanked 101 Times in 32 Posts	Re: NAD :: 1969 Ace Tone 601 50w Tube Head By the accounts I have seen all over the builder's forums the new issue 7591's are good, apparently very good. The vintage 7591 tubes were going literally insane in price before the new ones came out. There were all sorts of stories, including the one detailed on Geofx about one man buying nearly every one available through various sources to keep in Japan, or in his stash. Here's the quote, true or not: Cautionary Tubes - these are very hard to find 7591/7591A - legend has it that these otherwise excellent tubes were all bought up by an oriental buyer who toured the USA paying cash for all of them he could find, then disappearing. You are likely to only find used ones or the odd pair in some out of the way place. Dealers will in general not have them. I have personally seen trays full of NOS 7591A's for sale in the Akihabra electronics district in Tokyo, lending some credence to the rumor. Brought the prices right back in line when the new ones came out.

01-29-2011, 07:42 PM	#8 (permalink)
Udonitron Oh Great...99 Yen!? Join Date: Aug 2009 Location: On an Island in BC Posts: 11,167 Thanks: 25 Thanked 56 Times in 23 Posts	Re: NAD :: 1969 Ace Tone 601 50w Tube Head NP Wulf! Welcome aboard Yeah I read that Cygnus Interesting but I am happy they re-released them You can get a matching set of JJ's for about $40 shipped. __________________ Tales From The Woodheap Flickr

01-29-2011, 10:28 PM	#9 (permalink)
Udonitron Oh Great...99 Yen!? Join Date: Aug 2009 Location: On an Island in BC Posts: 11,167 Thanks: 25 Thanked 56 Times in 23 Posts	Re: NAD :: 1969 Ace Tone 601 50w Tube Head Hey Cygnus So the caps in that are 2 x 250v 100uf & 2 x 350v 20uf (more $$ for those) Do you suggest I replace them underneath with these and leave the stock caps there for originality? Cheers 3 NOS Sprague ATOM Capacitor Electrolytic 250V 100uf on eBay.ca (item 120677140735 end time 01-Feb-11 15:12:31 EST) New 1 pc. 20uF 350V Axial Electrolytic Capacitor 20mfd on eBay.ca (item 130479617121 end time 25-Feb-11 10:10:38 EST) __________________ Tales From The Woodheap Flickr

02-01-2011, 03:56 PM	#12 (permalink)
Udonitron Oh Great...99 Yen!? Join Date: Aug 2009 Location: On an Island in BC Posts: 11,167 Thanks: 25 Thanked 56 Times in 23 Posts	Re: NAD :: 1969 Ace Tone 601 50w Tube Head The current cap cans are not budged at all however but no clue on the condition and the amp has not been plugged in while I have owned it so they are all nice and discharged. Good time to replace em __________________ Tales From The Woodheap Flickr

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