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Hoffman Amps Forum image Author Topic: Need suggestions on AA 864 quality premium components.  (Read 3556 times)

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Offline tubes2bits

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Need suggestions on AA 864 quality premium components.
« on: January 27, 2011, 01:14:26 pm »
I plan to build a Fender Bassman AA 864 circuit amp. I would like to hear some suggestions on a quality parts list. What preminum components would you recommend?

Offline sluckey

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Re: Need suggestions on AA 864 quality premium components.
« Reply #1 on: January 27, 2011, 01:55:34 pm »
Doug has all the premium parts you need to build this amp. Just look at the top of this page. And you can get a replica set of boards from http://www.turretboards.com/
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline Fresh_Start

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Re: Need suggestions on AA 864 quality premium components.
« Reply #2 on: January 27, 2011, 02:02:38 pm »
Look at the top of this page.  You can rely on Mr. Hoffman to offer only high quality parts.

IMHO transformers and tubes are the most critical components in terms of quality.  

Doug Hoffman's transformers are excellent in my experience.  

If I were you, I'd get some cheap Chinese 6L6 power tubes for testing and a pair of Svetlana "Winged C" 6L6s for the final product.  You can still get an NOS 12AT7 fairly cheap.  Hoffman stocks them IIRC.  12AX7 preamp tubes can go from $7 to $150.  Do some research here and elsewhere.  First tube in the signal chain has the biggest effect in my experience.  (Hoffman's tubes work fine - I just think this is one area where Mojo really exists.)

Resistors:  Fender used carbon comp throughout.  Metal films make less noise.  Go to Aiken Amps - info section for good article.  Type doesn't really matter.  Wattage rating does - 1/2 watt unless otherwise specified.  Oh, and you may need wirewound resistors for 3 and 5 watt values.

Capacitors:  cork sniffers can argue for days about these.  Silver mica for tiny values.  Polyester film (Mallory 150) or Polypropylene film (Orange Drop) for coupling & signal caps.  Hoffman's electrolytic caps are fine.  You could go with  F&T electrolytics if you think it matters.

Switches:  Carling.

Jacks:  Switchcraft or Neutrik (make sure it's not their budget version though)

sluckey's right about boards from TurretBoards.com.  Good stuff!

Feel free to disagree - these are just my opinions and everybody has one!  :wink:

Chip
Quote from: jjasilli
We have proven once again no plan survives contact with the enemy, or in this case, with the amp.

Quote from: PRR
Plan to be wrong about something.

Offline tubes2bits

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Re: Need suggestions on AA 864 quality premium components.
« Reply #3 on: January 27, 2011, 03:59:19 pm »
Thanks, Sluckey and Fresh Start.  This has proven to be a good jumping off point for me in gathering information.  Some boards are a waste of time. :sad:  I'm glad I found this one.  :grin:

Offline bluesbear

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Re: Need suggestions on AA 864 quality premium components.
« Reply #4 on: January 28, 2011, 10:32:50 am »
If you take every word so far as gospel, you won't be disappointed. If you're building one amp, you won't beat Doug's prices. Although I make my own boards, I buy the materials at turretboards. Good stuff. As Fresh_Start says, you'll never get agreement on caps. I recommend Mallory's. I like 'em and they're so much smaller. You never know with tubes because they vary so much from batch to batch within each factory. Get a good brand (anything from Doug) and you'll be alright.
Good building!
Dave

Offline 38Super

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Re: Need suggestions on AA 864 quality premium components.
« Reply #5 on: January 28, 2011, 08:26:54 pm »
The advice I have just read reminds me I need to get off the computer and get back to work on my current project   :wink:

I have had good results with Xicon and Nichicon polypropylene caps in addition to 715 series orange drops.  I use a combination of the two and prefer the sound over Mallory 150s: that's my taste.

Suggest using 1W plate load resistors for reliability.  The thing is I have never had to repair one of my amps due to component failure.  I wouldn't recommend spending extra money on carbon comp resistors.  Vintage amp makers used them because it was the technology of the day.

Have tried NOS RCAs, NOS Amperex, JJs and I have found Tung-Sol 12AX7s give me the best tone.  You aren't going to be able to find your sound without a little experimentation.  Be careful about developing a taste for expensive NOS tubes: they'll can only improve a good build: they aren't magic. 

Some guys out there swear by Edcor and Heyboer trannies.  Don't know who Doug works with for trannies.  You might have to do several builds to figure out exactly where your tastes lie.   :shocked:

rob

Offline bluesbear

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Re: Need suggestions on AA 864 quality premium components.
« Reply #6 on: January 29, 2011, 07:41:46 am »
I like Xicon caps, too. Also Tung Sol 12AX7's. I NEVER use NOS tubes. The ones that are left are mostly noisy crap and it's too hard to replace them with something that sounds the same. Design the amp for what's available and you won't have that problem. That's really what Leo did and it worked for him. Carbon comps aren't expensive if you buy them in bulk. I get them 100 for $10.
I was in a band for a few years that played 4 or 5 nights a week. The other guitar player was always after me to buy a new factory made amp because they had a warrantee. He had more money than sense, I think, because he never got it. Every time one of his amps broke down, he had to finish the night with the little extra amp I bring. He never brought an extra. Mine never broke down, although I had a tube fail. Once. What do I want a warrantee for?
Dave

Offline stingray_65

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Re: Need suggestions on AA 864 quality premium components.
« Reply #7 on: January 29, 2011, 03:59:18 pm »
tubes2,

Now this is my small take on things.

****OPINION ALERT**** TAKE NONE OF THIS AS FACT OR DIRECTED AT ANY PERSON***

As a novice amp builder I mistakenly listened to a lot of info about "quality" parts that had its roots in HiFi.

I've found that "quality" parts in guitar amp building = long life. "quality" parts in HiFi = tonal transparency.

Guitar amps in general "color" and "change" the tone of the guitar signal. different parts, I should say differnt brands, will color the sound differently (caps, resistors iron etc).

The topography of the amp determines the over-all tone.

The small stuff is pretty easy to change and not very expensive. A lot of times parts can be wired in with a switch so you can get an A/B comparison so you'll KNOW if you like an O drop or a 150 in that particular spot, or as a lot of us have decided it may make no change at all!

You can also play around with values that way too, maybe you want a little more or less high roll off, change the value.

I do not want to speak for Chip or the others when they say Doug sells high quality parts, I interpret that as saying he sells parts that will last for ages.

I will agree whole heartedly with them.

Don't let others dictate what sounds good to you, You'll miss out on a lot of good stuff if you do.

If you're looking to build your opus, start with a good foundation of transformers and turret board. the rest changes so easily to suit your tastes.

Just my opinions so do what you will with them.

Ray



 
My mind is aglow with whirling, transient nodes of thought careening through a cosmic vapor of invention (H. Lamarr)

 


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