Why are tube amps better? (1 Viewer)

[Frank_S]

Saurav,

The easiest way to achieve this hookup is to run the preouts from your receiver/pre-pro/AV-preamp/whatever (i.e., the piece that does the multi-channel processing) into one of the inputs on your tube preamp. Your 'critical' music sources go straight to your tube preamp. The outputs of your preamp then go to the amps driving the front speakers. No need to swap interconnects. For HT, you now have 2 volume controls, so you either find the level on the tube preamp's control which gives you 'unity gain' (easy to do if you have an SPL meter)

Since I use 2 preamps in my system, I'm interested in following this approach. So you're sure there is no harm in running the L/R preouts of the HT pre/pro into any SOURCE input of the 2 channel preamp?, note that I said source input.

 

[Saurav]

So you're sure there is no harm in running the L/R preouts of the HT pre/pro into any SOURCE input of the 2 channel preamp?, note that I said source input.

Nope. It's a line level signal. Think about it this way - if your CD player had its own volume control, you could connect it directly to your power amps. Or, if you decided you didn't need volume controls at all and you're happy with your system playing at full volume all the time, you could do the same thing. So, an input is an input, I'm not sure what you mean by 'source input'. For all intents and purposes, the input on your power amp is identical to the input on your preamp - high impedance, and capable of handling line level signals. You'd run into trouble if you connected 2 inputs or 2 outputs to each other, but you're not doing that here.

I had my integrated amp's preamp section hooked up this way, and AFAIK many people have their HT and 2-channel systems integrated this way.

 

[AjayM]

A little test. Pick the Solid State amp....
Amp A
Power Output: 220 watts continuous at 8 Ohms
Distortion: less than 1% 20 Hz to 20 kHz @ 220 watts output
Frequency Response: 5 Hz to 75 kHz @ -0.5 dB
Input Sensitivity: 2.2V RMS
Hum and Noise:110 dB at 220 watt output
Weight (approx.): 100 lbs each
Amp B
Power Output: 150 w @ 8 ohms
Distortion: 20 Hz–20 kHz with no more than 0.3% THD
Frequency Response: within 0.1 dB from 20 Hz to 20 kHz
Input Sensitivity: 1.59V for full rated output
Hum and Noise:-75 dB CCIR
Weight (approx.): 220 lbs. each
Andrew

 

[Saurav]

Wow, that's interesting. My guess for SS would be amp B. Or is it amp A I wonder if knowing the prices would make a difference. Just goes to show how little you can tell of a piece of equipment just from its numbers, especially when the manufacturer's name is removed from the equation.
OK, I change my mind, my guess is amp A

 

[Doug_B]

Saurov and Keith,

Thanks for the info. I had a mental image of figuring out how the tube pre would feed the multich pre, so I blanked out on the reverse being a possibility, given that the music source would feed the tube pre.

Given my uncertainty as to whether there would be any actual benefit for me in doing this, I'm not sure I'd want to spend 4 figures on something. Maybe up to $500 I could deal with as a near term "experiment". I'm not sure if a kit would be up my alley; I'd have to see what was involved, as I would consider myself semi-competent in this area (fine soldering may be tough - I need some space for mistakes). What equipment is needed to put one together?

Also, do any of these pre's support 5.1 inputs (e.g., SACD)? Of course, I'd then have to run the other 3.1 output channels to my other amps (3 ch and sub amp) and do full 5.1 from my multich pre to the tube pre. Sounds like one too many 5.1 inputs for the tube pre. Maybe just running 2 channel SACD through the tube pre is the ticket.

Thanks again.

Doug

 

[Saurav]

Go to www.audioasylum.com and check out the Bottlehead forum. They sell a preamp kit called the Foreplay - $150 for the basic kit, $300 with upgrades. People with zero prior soldering experience have successfully built this, with no hum/buzz/hiss problems. The instructions are excellent, and you have a whole forum full of people, plus archived posts, for all the support you'd want. I built a Foreplay after around 7 years of not having touched a soldering iron, and it sounds beautiful. It was the most fun thing I've done in a long time, and I can totally vouch for how good it sounds. People say it sounds as good as some preamps in the $2K - 3K range - I wouldn't know since I haven't heard any, but I do know it sounds much better than the $300 preamps I've heard. Bottlehead's website is www.bottlehead.com and there's a link from the forum (and vice versa).

I had a mental image of figuring out how the tube pre would feed the multich pre, so I blanked out on the reverse being a possibility

I know what you mean, I slapped my head and felt pretty silly the first time I read about hooking it up 'backwards', wondering why I hadn't thought about it myself.
Multichannel - no idea, it's not an area I have any interest in at this point. You could in theory build 3 Foreplays (possibly in the same chassis) or buy 3 preamps, but I wonder if the effort would be lost on movies. Multi-channel SACD is a different issue.

 

[Doug_B]

Saurov,

Thanks again. Been reading stuff here and there about the Foreplay; could be worth a try.

I figured I'd need 3 of these pre's to satisfy multich SACD, although I'm curious as to whether the LFE channel would benefit from tubes vs just routing it from the source to the multich pre and then out to the sub amp.

Doug

 

[Saurav]

I doubt it. I just said 3 because it's easier to build or buy pairs of channels. You could see if Doc B. will sell you 2 1/2 Foreplay parts Some of the electronics is shared between the channels though, so you might need to redesign things a little bit if you decide to build a single channel FP. For instance, removing a tube changes the load on the power supply, and things like that.

 

[Duke H]

Thanks Jack,
Unfortunately, my car is S.O.L. That ends my tube amp venture. I'm selling most of my HT equipement on the HTF Market Place, if anyone's interested.:frowning: So long, Tube dreams of glowing tubes and analog warmth!

 

[John Sully]

Saurav,

Think about the tonearm/cartridge interaction as similar to the speaker suspension/cabinet interaction. In speakers this is a defining aspect of low frequency extension and articulation. Tonearms and cartridges react in much the same way and have a profound impact on the sound of a turntable/arm/cartridge combination. More so than any other factor in this system which I have auditioned for.

BTW, I gave up on vinyl almost 20 years ago. I found the superior dynamics and detail of CD much preferable. I did find that many of the early CD remasters and recordings were truly awful. However those that were good to great were awesome; much better than even the best vinyl I had heard on my system up until that time. Believe me, in the late 1970's and early 1980's the quality of vinyl pressings was at a nadir and I spent a lot of time hunting out Direct-to-Disk recordings and MoFi remasters (on vinyl) of good pop records.

 

[Saurav]

I guess it's all a matter of taste. I heard the SACD and vinyl version of the same album recently, on a system I would describe as being pretty close to state of the art. I preferred the vinyl, but there were several areas in which the SACD was definitely better.

Believe me, in the late 1970's and early 1980's the quality of vinyl pressings was at a nadir and I spent a lot of time hunting out Direct-to-Disk recordings and MoFi remasters (on vinyl) of good pop records.

I don't doubt that. Not much of the music I listen to comes from that period.

 

[AjayM]

Wow, that's interesting. My guess for SS would be amp B. Or is it amp A I wonder if knowing the prices would make a difference. Just goes to show how little you can tell of a piece of equipment just from its numbers, especially when the manufacturer's name is removed from the equation.

Well both of these are monoblock amps with 5 figure price tags. But I was chuckling at the lack of understanding of what a good tube amp is, people who don't know just assume that they have horrible specs, low power, lots of distortion, etc. And that's not the case all of the time.
How about another.
Amp A
Power: *** watts rms
Frequency resonse: 10 - 20 KHz (+/- 0.5 dB)
THD+N: 0.2% at full rated power into 8 ohms (1 KHz)
Input impedance: 100K ohms
Weight: 35 lbs
Amp B
Power Output: *** watts rms
Frequency Response: 5 Hz to 30 kHz (-0.5 dB points)
Distortion: less than 1% 20 Hz to 20 kHz
Input Impedance: 100K ohms
Weight (approx.): 50 lbs
These aren't priced in the stratosfear like the last 2 were, these are in a low 4-figure price range (like $2k). I've blanked out the power wattage as I think that will be a semi-easy give-away. But for some info on them, they are both over 50 Watts per channel and under 150 Watts per channel, so they are both more than adequate for even decently sensitive speakers.
So does anybody want to explain the rolled off highs and bass again?
Andrew