Dynaco st70 vs Heathkit W5M

[Rudes]

Can anyone tell me which they feel is a better overall sounding/built amp?

[planet10]

Both should really be considered as donors for a complete rebuild.

dave

[Vargas]

I personaly have done both and I really like the W5M's. I used the triodeel driver board and did all the usual upgrades on the St-70 and for the W5M's I just did some simple upgrades such replace all the electrolytics, metal film resistors, Hovland musicaps and a set of Golden dragon Kt-66's and I must say the W5M's sounded very nice! They even spent a week at the local Hi-Fi store for some auditioning. Either one will make a very nice amp/amp's. The St-70 is all on the same chassis and with the W5M's being monoblocks= two of them for stereo= twice the space and twice the upgrades. One thing to beware of though is that the W5M's are notorious for the power tranny going bad! It will happen, it's just a matter of time. Once this happens you are stuck with trying to find a original replacement. I personally liked the W5M's better. Just my .02 Cheers

[vinylkid58]

Originally Posted by Vargas

One thing to beware of though is that the W5M's are notorious for the power tranny going bad! It will happen, it's just a matter of time. Once this happens you are stuck with trying to find a original replacement.

Heathkit must have sold replacement PT's for a while. I've seen W5's with larger power transformers in square black boxes like the one that's on my W4. Mine has cloth covered leads, so it's not a newer model.

Jeff

[Rudes]

Thanks for the replies...I have 2 w5m amps with the larger output trans that I picked up at a garage sale for 10.00. The power trans was not working in one and I used a Hammond as a replacement. I just picked up a used original trans that I will install. I have one st-70 with the GSI Fuchs board and another with the VTA board. I have not hooked them up for comparison yet.

[planet10]

I should mention that Gregg-the-Geek brought an amp he calls DynaMutt based on an ST70 to the just passed VI diyFest. It was outstanding. I understand that new input boards will be available once he finsihes the R&D.

dave.

[vinylkid58]

Originally Posted by Rudes

The power trans was not working in one and I used a Hammond as a replacement.

I noticed that Hammond now list potted versions of their "classic" series trans. Coincidentally, they are very similar to the Heathkit's.

Jeff

[vinylkid58]

Originally Posted by planet10

I should mention that Gregg-the-Geek brought an amp he calls DynaMutt based on an ST70 to the just passed VI diyFest. It was outstanding. I understand that new input boards will be available once he finsihes the R&D.

It was most excellent, and seriously embarrassed a couple of new commercial amps.

Jeff

[planet10]

Jeff,

I think Chris' Joida is leaning towards this... if his falls, how far behind is yours?

dave

[vinylkid58]

Originally Posted by planet10

I think Chris' Joida is leaning towards this... if his falls, how far behind is yours?

Maybe not too far. Like the stock Dynaco, without a new chassis, it's pretty hard to go crazy. There isn't a lot of room for extra stuff. It's definitely going to get some CCS mods thou.

Jeff