All-tube system vs. Hybrid Tube-Solid State system?

[hnash53]

In terms of getting the "tube sound," is there anything to be gained (is that a pun?) by having an all-tube (tube preamp + tube amp) system over a hybrid tube-solid state system (tube preamp + solid state amp)?

Thanks for your comments.

 

[ferninando]

there is nothing better for pure tube sound than a tube preamp and tube poweramp or integ. amp. IMO.
THAT is pure tube sound.
tube mix'd with SS is not pure tube sound but a combination of the two. even tho the sound can be outstanding it is NOT pure tube. IMO.

 

[Selmerdave]

It depends what you like. It's possible that if you like tubes you prefer an all-tube system to a hybrid setup (I generally do) but it's certainly possible that the reverse is true. I generally don't subscribe to the notion that hybrid is "best of both worlds" or that one needs the other to make up for its shortcomings, both will sound good with appropriate speaker matching and high-quality components.

 

[ferninando]

right, both tube and SS can sound equally outstanding with good equipment.
I lived for 35 yrs with TOL SS gear.
today I revel in the sweetness of my all tube equipment and 1 good SS preamp, HK Cit 11.
sometimes I will mix my SS pre with my tube amps. sound is great.

 

[hnash53]

When it comes to tubes, here's what I've tried.

1. Nobsound tube preamp and a separate solid state power amp. Sounded good.
2. Nobsound hybrid: tube preamp + solid state amp all in one unit. Sounded good.

Guess I might need to try an all-tube system next.

I know that Nobsound is chinese stuff and I guess it sounds OK... but there hasn't been a big noticeable difference between the tube sound and solid state when I've listened to the two things above. And I would guess I should move a little higher in quality /manufacturer.

Next thing is to try an all-tube unit and see if I can tell the difference between it and solid state.

Thanks for your comments.

 

[Funky54]

Another factor can be speakers. Mine require a lot of juice, so tube becomes expensive. I use a tube pre with solid power. The tube preamp sounds much warmer without loss of detail to me over the Solid State pre.

I think it's worth considering just using a tube pre. If I had the coin I would try all tube.

I will say this. I have a lot more experience with solid state than tube and I'll never go back to SS pre.

 

[nj pheonix]

Too broad a question. I'm very pleased with my tube set up. I'm also very pleased with my SS set up. If executed properly great results can come from either. If executed poorly , poor results can come from either. Throw in synergy of various speakers and personal taste, along with your listening room and the results can be endless. This can be polarizing but there really is no need for it. There is more than one right path . my 2c

 

[markus]

it is so dependent on the speakers. That being said I used to play with a nice Fisher solid-state receiver from the 70's which had pre outs and run that to a tube amplifier du jour. speakers were usually vintage KLH or other brands and a lot of vintage open baffle stuff....

but I could roll tube amps through the system and keep the conveniencee a 'modern' receiver but I could roll tube amps through the system.....

 

[hnash53]

As for speakers, here's what I have:

1. Front pair of Infinity RS 5b's. 4 ohm. Great speakers.
2. Rear pair of Polk Monitor 40's. 8 ohm. Decent speakers.

I may switch to a better matched pair of rear speakers.

With 2-channel tube equipment, I also connect a Dynaco Quadapter to give me simulated 4-channel surround when watching movies, and the ambience is also nice when listening to 2-channel sources.

The hybrid tube amp I have now is rated 4-8 ohms.

 

[markus]

Sweet. Those are nice speakers...... The only downside of newer speakers, is (usually) they aren't as efficient as the oLd school papercone fullrange drivers, so with those speakers you're best doing the tube pre / ss amp unless you have bottomless pockets.

 

[seta1]

In terms of getting the "tube sound," is there anything to be gained (is that a pun?) by having an all-tube (tube preamp + tube amp) system over a hybrid tube-solid state system (tube preamp + solid state amp)?

Thanks for your comments.

Hi,

At present I have a McIntosh C26 attached to a nice Pilot EL84 stereo power amp. That system sounds amazing. It belongs to a friend and I just finished refurbishing both units. Another system I am working on has one of my rebuilt Dynaco PAS-2 preamps driving a McIntosh MC2205 amplifier and again, the system sounds quite nice. Then there is the all tube system consisting of a pair of my own design class A EL34 mono power amps and a HH Scott LC-21 preamp. All these systems sound a little different, but all sound really nice and none of the systems produce any ear fatigue. So, in my world, it is more about the quality of the components used and not whether it is tube or solid state. I have heard good and bad in both. In my years of servicing audio, my favorite solid state amps are McIntosh followed by Threshold. For tube the hands down best sounding amp has been the older Audio Aero Capitole power amp that uses a pair of EL34's in push pull parallel with a pair of 6550's in each channel. Second best has been the Jadis Defy-7.

 

[santa]

I think the best way to go here is use the best type of device where it belongs in the circuit
Valves for voltage gain and SS devices for current gain AKA Hybrid Amplification.
To really pull this off you need to operate the finals in Class A to get the best from the SS type devices.
The Moskido is an excellent example of this

 

[Selmerdave]

Hi,

At present I have a McIntosh C26 attached to a nice Pilot EL84 stereo power amp. That system sounds amazing. It belongs to a friend and I just finished refurbishing both units. Another system I am working on has one of my rebuilt Dynaco PAS-2 preamps driving a McIntosh MC2205 amplifier and again, the system sounds quite nice. Then there is the all tube system consisting of a pair of my own design class A EL34 mono power amps and a HH Scott LC-21 preamp. All these systems sound a little different, but all sound really nice and none of the systems produce any ear fatigue. So, in my world, it is more about the quality of the components used and not whether it is tube or solid state. I have heard good and bad in both. In my years of servicing audio, my favorite solid state amps are McIntosh followed by Threshold. For tube the hands down best sounding amp has been the older Audio Aero Capitole power amp that uses a pair of EL34's in push pull parallel with a pair of 6550's in each channel. Second best has been the Jadis Defy-7.

Seta do you have any experience servicing the Capitale? A friend has one and it has a slight hum in one channel. I have the service manual but haven't been able to figure anything out yet... Maybe best for pm or a new thread.

 

[for_p1]

If you must have tubes, they should be in power amplifier. Interaction between speakers and tube amp is wat produces specific "tubey" sound. Preamp is better to keep solid state, more so if you want tone controls. Tone adjustments circuits are hard to implement and commonly very poor in tube designs.

 

[seta1]

Seta do you have any experience servicing the Capitale? A friend has one and it has a slight hum in one channel. I have the service manual but haven't been able to figure anything out yet... Maybe best for pm or a new thread.

Hi
I have worked on a few. Most common problems are blown bridge rectifiers in the power supply and
bad or noisy 6SN7's The amp is like any tube amp in that any tube with excess gas can cause hum as
well as a soft and distorted sound. I would first try swapping tubes channel to channel and see if the hum follows a tube.
Failing that, I would check the power supply capacitors and all sections of the power supply. Although on one board, that power supply is not just a simple single bridge rectifier feeding everything. There are four bridge rectifiers, if memory serves, and they feed different sections of each channel. It is possible for one channel to have a bad power supply capacitor. The main ones are black and stick through the chassis. Also, this amp uses two EL34's in push pull parallel with a pair of 6550's. Since it is self biasing, you must use those tubes, with 6550's closest to the output transformers and the EL34's between those and the 6SN7's. Just curious where you got a service manual? I had never been able to find even a schematic for the Capitole or any other Audio Aero product. I believe Audio Aero used that same name on another product. A CD player, I believe. The unit I speak of is a big power amp using two 6SN7's as driver and phase splitter tubes, and a pair of EL34's in parallel with a pair of 6550's for output tubes. What kind of speakers does this person use? I ask because even when running correctly, the amp is not dead silent through speakers like Klipsch or other high efficient speakers. Make sure you use a shorting plug in each channel when testing for noise. Many times people blame the power amp when the problem is a faulty interconnect or other device upstream in the audio signal path.

 

[Selmerdave]

Hi
I have worked on a few. Most common problems are blown bridge rectifiers in the power supply and
bad or noisy 6SN7's The amp is like any tube amp in that any tube with excess gas can cause hum as
well as a soft and distorted sound. I would first try swapping tubes channel to channel and see if the hum follows a tube.
Failing that, I would check the power supply capacitors and all sections of the power supply. Although on one board, that power supply is not just a simple single bridge rectifier feeding everything. There are four bridge rectifiers, if memory serves, and they feed different sections of each channel. It is possible for one channel to have a bad power supply capacitor. The main ones are black and stick through the chassis. Also, this amp uses two EL34's in push pull parallel with a pair of 6550's. Since it is self biasing, you must use those tubes, with 6550's closest to the output transformers and the EL34's between those and the 6SN7's. Just curious where you got a service manual? I had never been able to find even a schematic for the Capitole or any other Audio Aero product. I believe Audio Aero used that same name on another product. A CD player, I believe. The unit I speak of is a big power amp using two 6SN7's as driver and phase splitter tubes, and a pair of EL34's in parallel with a pair of 6550's for output tubes. What kind of speakers does this person use? I ask because even when running correctly, the amp is not dead silent through speakers like Klipsch or other high efficient speakers. Make sure you use a shorting plug in each channel when testing for noise. Many times people blame the power amp when the problem is a faulty interconnect or other device upstream in the audio signal path.

Thanks! Wow, I just looked and you are right, the EL34's are in parallel with the KT88's! That is very odd, I hadn't realized that before, I can't quite get my brain around that. In this case he has 6L6's and 6550's. I wonder if the issue is in the interaction of those tubes, but I have switched all tubes around and it doesn't move or change. Thanks for the info.

 

[Hyfi]

I have run several combinations over the years.

Started out with all SS, Hafler 945 / 9180
Swapped the Pre for a Sound Valves 101i all tube pre - nice improvement to me
Swapped out the Hafler 9180 for an Odyssey Stratos+ for more control and bass
Swapped out the SV101i with a VAC CLA1MKII dual mono all tube pre for a huge gain in tube sound which got better with rolling tubes
Swapped out the Stratos for a Counterpoint NPS-400, which is a Hybrid Amp, Tube input / SS Output

Speakers used were Dynaudio Audience 82s and Clearfield Continentals

2 systems current are Hafler 945-Stratos-Dynaudio and VAC-Couterpoint-Clearfields

I love both setups for the same reasons people choose one over the other. The tube setup is airy, detailed, and has great mid-range. SS setup is power, bass, and fast.

 

[seta1]

Thanks! Wow, I just looked and you are right, the EL34's are in parallel with the KT88's! That is very odd, I hadn't realized that before, I can't quite get my brain around that. In this case he has 6L6's and 6550's. I wonder if the issue is in the interaction of those tubes, but I have switched all tubes around and it doesn't move or change. Thanks for the info.

I would change those 6L6's out and put EL34's back in the amp. I believe the EL34's are running class A and triode connected with the 6550's being
pentode connected if memory serves. The amp puts out 50 watts a channel. I have built a couple amps using pairs of EL34's in parallel with pairs of KT66's.
Those amps sound amazing. But in the case of my own amps, All tubes are biased class A and run in pentode mode. It is a similar setup to the Aero. You
have to have separate biasing for each tube type.
I would check and or replace those big power supply capacitors. If one is bad, replace them all. The Capitole runs rather hot so it would not be unreasonable to have one or several bad power supply capacitors. On the power supply board, you will find some 800 piv bridge rectifiers. I generally replace them with 1000 - 1200 PIV bridges that also have a slightly higher current rating. The Capitole is notorious for blowing these bridge rectifiers in areas where power surges are common. In Europe,t he amps run on 220 volts (they were made and designed in France) and the power surges are only multiplied by a factor of two where as in the USA, they set the amps to 120 volts and power surge voltages are multiplied by a factor of four and when that happens, the bridge rectifiers at only a 800 PIV rating will smoke. The usual symptom is the amp blowing it's mains fuse at power on. There are also some power resistors on that power supply board. When you pull that board, check their solder joints. This board is known to have issues with the power resistor solder joints. Oh, the wiring to the power supply is soldered on or uses screw terminals, depending on the generation of the amp. . No plugs and jacks. So make sure you take a picture or draw a diagram so you can install the wiring correctly when you are done. You don't want to mix up any of those wires from the power transformer, or any that go to the amp boards. These are fantastic amps and well worth getting up and running properly. Oh, make sure when the amp is running that you have a LOT of space around it so it can properly ventilate.

 

[seta1]

With respect to tube verses solid state and the mix and match, I am presently listening to a Jadis Defy-7 i just picked up and I drove it with
a McIntosh C26 as well as an AE-ONE preamp (made by Cary Audio). I prefer the tube AE-ONE preamp. The C-26 sounded amazing with a
McIntosh MC2205 but not so amazing with the Jadis as compared to using the Jadis with the AE-ONE. Actually the Jadis sounded the most open using
my own design passive preamp that uses all solid silver wire and a silver contact stepped attenuator. I have used several different preamps both solid state and tube and each has it's merits. But the big thing is that components all have certain input and output impedances. Mismatch those and you end up with
sound quality that is lacking. Usual thing I find is that when using a tube preamp with a solid state amp, you run into the most trouble unless the tube preamp
has a strong cathode follower output stage that can drive a low impedance input power amp. Now, not all solid state amplifiers are low impedance at the input.
but most are under 100K ohms and most tube preamps, especially vintage ones, seem happiest with 50 - 100K loads on their output sections. When ever you mix and match different brands of amps with different brands of preamps you always run the risk of sonic issues. I have been using vacuum tube audio since I was a kid ( and yes I am an old fart who still remembers Jack Kennedy's election). I still feel vacuum tube audio offers the best compromise between accuracy and low ear fatigue. Certain modern amps, like my Jadis Defy-7 and the Audio Aero Capitole sound better then any vintage amp to my ears. but not all modern tube amps sound that good. Quicksilver amps are excellent sounding as are the Mystere and Primaluna amps. There are a lot of inexpensive Chinese tube amps that sound awful and are of very poor quality. Most notable are the Yaqin amps. But for the price, they are still better then the plethora of black box solid state 'home theater' gear out there. Some stuff that did not impress was Anthem. It is not bad and the quality is a cut above, but at prices as high as McIntosh, the McIntosh gear is so much better built and sounds so much better that it is a no brainer to go with McIntosh. In fact, I consider McIntosh the finest audio made today. And I have used a lot of expensive stuff and worked on it as well. The McIntosh stuff just sounds better. I could be happy with just about anything they make.
One of my favorites is the MA7000 integrated amp. That thing just plain sounds right. An absolutely beautifully designed and built amp that performs. If you have issues with that amp, you either need new speakers, a new signal source or new ears. There is something magical about McIntosh solid state amps that use their autoformer output section. I never really had much access to their stuff until I started working on it for a hifi shop in my area that sells their gear. Man was I impressed. Just wish I had the cash to buy something like the MA7000.

 

[derekva]

My $0.02. I've done tube preamp + SS power amp (Lazarus Cascade Basic into Robertson 4010), tube preamp into tube power amp (Aikido LV into various tube amps, some of which are in my signature), and various solid state preamplifiers into tube power amps (Kenwood C2 Basic / Denon PRA-1000 / APT Holman into various tube amps, all of which are in my signature). I've found in general, I prefer solid state preamps into tube power amps - mostly because I'm very sensitive to hum / tube hiss which is harder to purge from a preamplifier (because it operates in millivolt territory). That being said, the Aikido LV, which has no noise whatsoever, is on par with the solid-state preamplifiers.

So what does this mean? Try various combinations if you can and see what you like.

-D