tominredbank

Overall Rating
 5 of 5

Value Rating
 5 of 5

Used product for
1 to 3 months

Visitors rate this review
1.00 of 5, 3.00 votes

Price Paid:  $695.00 from Bob Latino Mods

Summary:
This review is for the Dynaco ST-70 in kit form offered by Bob Latino. I was searching for Dynaco amps on Audiogon and came across an ad for NEW Dynaco ST-70 kits. The kit uses all new parts (stainless steel chassis WOW!) and modifications in crucial areas also. The driver board is upgraded to use 3 -12at7`s and has a bias adjustment for all 4 power tubes. I had to give it a try. I called Bob and had it at my door in 3 days. The kit was a joy to assemble. ( I`ve never done one before) Step by step instructions and a color pictorial, After 100 hours burn in I was amazed. I`ve been in this hobby / obsession for over 40 years and never heard such a smooth but still detailed sound. Being a tweakaholic I called Bob to see if I could get my hands into it and make my own mods. Shortly after I had 4 Russian PIO caps at my door. Again a 100 hr. burnin and the sound was even more detailed, A distinct "punch" to the bass, layers of TEXTURE to instruments, unbelievable. ( to potential buyers I would go with these caps from the start)To top it off , changed out the 3- 12at7`s with NOS GE triple mica, and the EL34`s to Electro Harmonics platinium matched from Upscale Audio and I`m set. The closest thing I`ve heard to tube sound is my Monarchy monoblocks and this little 1959 design puts it to shame. Considering the high cost of some good tube amps you absolutely can not do better than this.

Strengths:
Allows me to tweak for all I want ( isn`t that what it`s all about?) The most TEXTURED sound I`ve heard yet. That word is one that needs to be understood more in audio. Layers of sound in sax, guitar and bass. Not just tweaking up the amp to produce more artifical "detail"40 watts per channe lcan still comfortably drive most speakers

Weaknesses:
Aboslutely none. I can see why this amp has been so popular for so long

Similar Products Used:
Monarchy SE`100 delux, Monarchy SM-70 Pro, Plinius, Exposure, Naim

scarey

Overall Rating
 5 of 5

Value Rating
 5 of 5

Used product for
More than 1 year

Visitors rate this review
3.00 of 5, 2.00 votes

Price Paid:  $565.00 from Ebay

Summary:
Here I have a QEI Modified stereo 70 also equipped with a Joe Curcio Premium Mod. I need to find schematics on the QEI quantum electronics Mod Called BIG CAPS.. Best sounding Amp i Have Ever heard especially the price...

Strengths:
Better sounding everytime i roll my tubes... Bass HA sounds like it is supposed to. no boomieness just there as it was recorded. MUST be the cables :)

Weaknesses:
None well except the fuse in rear where the iec plug goes.

Similar Products Used:
You Name it

Price Paid:  $0.00 from Gift

Summary:
Hello! I live in Israel and the unit is the Newer Series 2 under Panor Owners was received together with a ARC-SP-9 also series 2 preamp. Together only one word: SUPERB Original "National" brand made by the German factory Siemens EL-34 tubes, I also changed the Chinese driver by American ones Raytheon. Perfect match with my Gifted ARC-SP-9 Mk-2 preamp.

Strengths:
Reliable Amazing sound Full body sound Natural sound

Weaknesses:
NONE!

Similar Products Used:
Marantz 8b power Quad 306 SS power Rotel SS power

Price Paid:  $200.00 from eBay auction

Summary:
The ST-70 is an excellent amplifier, with a clean, well-defined warm sound. It should be known, however, that in order to achieve the performance of this amp I had to spend an additional $200 or so for new capacitors, switches, power cord, RCA inputs, output binding posts, one tube (7199), and a driver board cover. I also spent a week replacing components and polishing/painting the chassis and tube cage. Although there are an overabundance of mod kits for the ST-70, I left the circuit design completely stock. I've tried some of the mods in the past, and personally I feel that the 7199 tubes (designed specifically for audio) are sonically superior to any other signal tube being utilized in a mod kit. The Dynaco is an excellent choice for any audio system, especially for the budget-minded individual. Unfortunately demand for this amp has greatly increased, but the supply is there. They can usually be purchased on eBay for around $350, but I recommend looking for an original, unmodified amp. (I'm a little leary of the electronic knowledge of others, not to mention their soldering skills!) I'm rating the value a 4 out of 5 simply for the fact that 10 years ago this same amp in the same condition could be purchased for $25 at your local Goodwill or pawn shop. It gets a 5 out of 5 overall, but again consider the fact that I put a lot of time, effort, and money into my amp to acheive great performance. P.S. I don't mind answering questions/swapping photos/talking shop with others - email weedzie1@yahoo.com

Strengths:
Built like a tank Excellent power & output trannys (cloth) Virtually no audible signal distortion with properly matched and biased tubes Hum is absolutely inaudible over signal Elegant, classic styling

Weaknesses:
Lacking in the bass department (actually it's just fine; over the last 15-20 years the audio industry has convinced us that thumping, overpowering bass is "normal" and should be the main criteria in determining what makes a good amp/sound system. Original components are mediocre at best, although even the best components found in more expensive amps of the same era weren't meant to last 40 years! Crappy input/output terminals, slide switches, and power cord No driver board cover on early models Nickel plating not as shiny as chrome

Similar Products Used:
All kinds of tube and ss gear (I'm currently using a Dyna PAS 2 with this amp)

Price Paid:  $180.00 from Ebay

Summary:
I must agree these amps have some of the best transformers available for such a cheap price. The tube characteristic sound is truly there, but the stock unit is far from audiophile quality. After listening for a few days the deficiencies of the amp showed up more and more; sloppy bass, compressed midrange, diminished soundstage, fair dynamics, blurred instrument separation. You know what's next, modification of course! With a new constant current cascode driver board and regulated power supplies, and yeah the old shiny cap can had to go. The new capacitor bank has higher capacity and voltage rating. You can us you pick of driver tubes - 6DJ8, 6922 or 6N1P. Email me for pictures.

Strengths:
Transformers

Weaknesses:
Bass, dynamics, midrange.

Similar Products Used:
Conrod Johnson, Audio Research, Quick Silver