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Old 13th February 2003, 01:56 PM   #1
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Default to DIY or not to DIY

Alright....i'm trying to progress on my goal of a pair of 300b monoblocks. I've got my parts list, which i've priced all out at Angela online ....and i've come up with $750-800 not including tubes or the materials i'll use for the chassis. ( sidenote : i'm thinking about using black acrylic similar to Peter's Gainclone in the "this is not just another gainclone" thread. Your thoughts on this? )

Anyways, i'm looking around at ebay, and i'm seeing pairs of 300b monoblocks going for $750 a pair .....such as these
http://cgi.ebay.com/ws/eBayISAPI.dll...category=14973


I dunno....i'm half tempted to just buy these things outright...get down to the listening, and then upgrade the invidual passive components after my ears have gotten used to the sound........

whats you opinion?

-maz
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Old 13th February 2003, 02:04 PM   #2
Joel is offline Joel  United States
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Default Re: to DIY or not to DIY

Quote:
Originally posted by Magnetmaz
...and then upgrade the individual passive components...
whats your opinion?
That this is a total waste of time, and you should not turn into one of 'those people'. You want to "upgrade", fine, start playing with voltages, start changing values, add henries, etc. Switching brands of capacitor is bullsh*t.

The monoblocks looks decent enough - and they have a money back gaurantee, so why not? They don't come with tubes though. So, that will be a bunch more.
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Old 13th February 2003, 02:13 PM   #3
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That is not such a bad idea at all. After having done diy myself and enjoying it very much. I am however sometimes tempted to buy a kit.

I don't completely agree with Joel. The part I agree with is that you should first change values, voltages and currents..etc..

But I would also change passives. Black Gate NH and Auricap for coupling from one stage to the other convinced me. All together these 2 changes cost me $60 but "bought" me a $1000 dollar improvent so to speak.

The schematic is 90% of the sound but...the last 10% is the most difficult part to improve on and good passives can make a massive difference.

To boot ..good passives don't nessesarily have to be expensive. But you could for instance try to ccs load the driver stage..cost 30$ if you get something like K&K audio CCS. Or choke load with the chokes Joel and others have had such succes with.

Cheers,
Bas
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Old 13th February 2003, 02:13 PM   #4
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well, what if the chucklehead that built them used crappy guts?

If i priced the parts ( which were moderate quality...mostly angela stuff....paper in oil caps, hammond trannies, riken ohm resistors..etc) to cost the same as the finished product...where is he cutting corners to achieve the same result??

Being a guitar amp enthusiast, i can certainly put creedence in using the right type of vintage caps to achieve a better sound..... if this holds true in a 60W amp with a tone you want to be colored, how could this not hold true in an 8W/ch amp with a linear, clean sound as the desired result?


enlighten me, please, ....and pray with me that years of binge drinking hasn't damaged the aural center of my brain.

-Maz
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Old 13th February 2003, 02:31 PM   #5
Joel is offline Joel  United States
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Quote:
Originally posted by Magnetmaz
Being a guitar amp enthusiast, i can certainly put creedence in using the right type of vintage caps to achieve a better sound.....
Maz, don't get me started on guitar amps. I love them, I love electric guitars, and I love the sound. BUT, guitar players are iodiots when it comes to electronics, they are easily swayed by magazine articles, and they are extremely fashion conscious.

I built a Deluxe Reverb clone using $0.50 Xicon polester caps, and radio shack metal films (indonesian I believe). I practice at Smash Studios here in NYC, and often get comments on it - "man, that's 'vintage tone'!"... "sweet sound", etc.
The first iteration had NOS "Elemenco" paper tubulars from the 60's in it (I got them for almost nothing). When I swapped them for the Xicons, there was no change in sound whatsoever, and the reliability of the amp went up by 500%.
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Old 13th February 2003, 02:40 PM   #6
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i'm certainly glad to have your opinions, joel....as you seem to be one of the more outpoken people in the tube section ( if not the only one who responds to my inane posts )


while i have your attention, give me your opinions on 2 things:

1) the thing i mentioned in the first post about building the chassis out of black acrylic...probably with the exception of the top plate, which would be polished aluminum.

2) I've got an increasing interest in the dynaco St-70 amp. What is your opinion on this amp? I am contemplating buying one of these off ebay as well, since it seems to be such a classic. What is the difference in tonality between one of these and a pair of 300b monoblocks?
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Old 13th February 2003, 03:41 PM   #7
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Default DIY.

Hi,


Quote:
1) the thing i mentioned in the first post about building the chassis out of black acrylic...probably with the exception of the top plate, which would be polished aluminum.
1)Keep in mind that acrylic is harder to machine than wood or metal and that it should be treated against static electricity.
But,it can be done and should yield good looks to boot.


Quote:
2) I've got an increasing interest in the dynaco St-70 amp. What is your opinion on this amp? I am contemplating buying one of these off ebay as well, since it seems to be such a classic. What is the difference in tonality between one of these and a pair of 300b monoblocks?
2)Those are two totally different approaches to audio and your choice may very well depend on the type of speakers you will hook up to the amps.
While the 300B is certainly a charming tube with fabulous midrange, it would benefit from a well regulated PSU and a CCS a la Gary Pimm may well provide you with a more solid sound to rock the boat.

To my ears most SET designs I have heard so far fall apart when the music gets tough on the PSU, that doesn't mean they can't be made to sing, just that it's not my cuppa.

Bas' advice is also an option,although I can hardly imagine someone building a 300B amp with off the shelf Ratshack components...most of this crowd go for something a bit more exotic.

As far as passive parts go,well I always hear a difference between one brand or another, most important of course is to get the circuit right in the first place.

Cheers,
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Frank
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Old 13th February 2003, 03:47 PM   #8
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Default ...Guitar amps...

Hi Joel,

I have to agree with your remarks about guitar amps... I've restored a few and found they sound as they should with modern standard capacitors and resistors. Mind you getting the right spec. speakers and output transformers is the art to getting the voice right - and that often means dumping the vintage one for a modern built to original spec one... The number of knackered OPT and speakers I've come across that leave a soft crappy sound with no bite...

Both my sons play guitar really well - really really well - so I stick to bass - don't get me started on bass guitars and amps. Why do most players rave about one tone Fender rubbish

What is your view on 'vintage' guitars (not acoustics)?

ciao

James
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Old 13th February 2003, 03:51 PM   #9
Joel is offline Joel  United States
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Quote:
Originally posted by Magnetmaz
...the thing i mentioned in the first post about building the chassis out of black acrylic...probably with the exception of the top plate, which would be polished aluminum.
Sounds cool to me. I recently saw somebody's amp on the Net that was made entirley of clear lucite. Very very cool. If I had more tools, I'd try that.

Quote:
I've got an increasing interest in the dynaco St-70 amp. What is your opinion on this amp?
The ST70 is the most popular tube amp, of any style, ever made. I think that says something. You really can't go wrong, and there is a wealth of mods and experience out there on those amps.

I've never heard a 300-B amp, so I can't comment on them.
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Old 13th February 2003, 03:59 PM   #10
Joel is offline Joel  United States
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Default Re: ...Guitar amps...

Quote:
Originally posted by James D.
What is your view on 'vintage' guitars (not acoustics)?
Hi James,
I've played a lot of guitars over the years, and I can honestly say that the new Gibsons and Fenders are every bit as worthy as "vintage" models.
I will not pay $10,000 for a slab of poplar, when I can get one made this year that sounds 99% the same to me.

Also, what most vintage guitar nuts forget is that, when their favorite artists were recording the classic songs in the 50's and 60's, they were using NEW guitars! Jimi Hendrix didn't use an old strat! He went to Manny's and grabbed one off the rack.

The best electric I've ever held in my hands is my 2002 Gibson 1958 Les Paul reissue, period.
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