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Magnavox 175 Tube preamp

Jbmorrey

Jbmorrey

Active Member
So I recently received a Magnavox 175 Tube amp, cleaned it up and added a wood base. I currently have it hooked up to a volume control and using it through a Project Phono preamp. My question is , I understand, or have read that the majority of the musicality and/ or warmth of a tube amp, comes out of the actual preamp, so matching a SS preamp(my Project Phono) to the Magnavox is not truly a pure Tube sound but simular to a hybrid.Am I understanding this correctly? I understand there is a Dynaco PAS tube preamp that works for the Maggie’s, but is there any other recommendations of a tube preamp that could also possibly have some tone controls.
Also, if I just went ahead and purchased a Tube Phono preamp, would that then create a “pure” tube sound? I am not sure if I am understanding this correctly, so please advise.

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Thanks,
James
 
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Also, another quick question, I was considering painting the power supply to a good deep black. Would painting be OK, and would i need to use a heat resistant paint like for BBQ’s?

Thanks again everyone.

James
 
Painting PT bells and laminations is fine, regular spray paint works well... I've used SS and tube pre amps,,, listen to them both and then decide... I use tube phono pre amps...
 
What is your source? I get the most tubey goodness from my source straight into the Magnavox amps, nothing between them. If your source has volume control than that is preamp enough. If I'm driving a speaker(s) that need more tone control, I use a preamp with tone controls.
To make the best sound, all the variables must be considered and tested (or researched,) Source, preamp, speakers. Say you found a tube preamp, say it does its thing the way it wants, sometimes the synergy is too tubey(distorted.) An excellent match for my Imperial 6 speakers is a Sansui 3300 solid state receiver with preamp out to a Magnavox 8601 single ended el84 tube power amp. The same amp sounds best with no preamp from the 8601 to a pair of traxials that like the 8601 without a tube preamp.
 
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I just realized your talking phono here. Not my forte. I can say that a tube unit be it preamp, amp or whatever, is a distortion inducing devise, be it yummy good distortion that doesn't harshly clip the music. Keep that in mind when thinking about your options and needs. Also, the impedance synergy can be what is the most important. I believe tube amps like a low impedance input.
 
knockbill said:
Painting PT bells and laminations is fine, regular spray paint works well... I've used SS and tube pre amps,,, listen to them both and then decide... I use tube phono pre amps...
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Ok thanks for the input on the Paint. I guess my question was if I am using a SS preamp for the phono, am I listening to a hybrid? Will a Tube pre for the phono make the system an "All Tube" and make a significant impact?

Thanks,
James
 
An Eico HF-85 is an all-tube preamp with a built-in phono stage and tone controls. It’s also just a generally very nice sounding preamp.

That being said, I wouldn’t get TOO caught up in all tube vs hybrid. I recently compared an all tube modern pre to a late ‘80’s SS preamp and the tube pre was less warm and not quite as full sounding as the SS pre, so if I were blindfolded, I probably would have guessed the tube unit was SS and vice versa.
 
captouch said:
An Eico HF-85 is an all-tube preamp with a built-in phono stage and tone controls. It’s also just a generally very nice sounding preamp.

That being said, I wouldn’t get TOO caught up in all tube vs hybrid. I recently compared an all tube modern pre to a late ‘80’s SS preamp and the tube pre was less warm and not quite as full sounding as the SS pre, so if I were blindfolded, I probably would have guessed the tube unit was SS and vice versa.
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Gotcha, so which 80’s SS pre were you referring to? My setup is a pair of Klipsch Forte and I hear nothing but good things in regards to Klipsch Heritage and Tubes, so this is why I am thinking all tubes, but I just need to try different things. I have a Pioneer sx950 that I might try as the pre to my Magnavox, wonder how that will work?

James
 
I picked up a Forte Model 2 here from Bartertown - it has nice weight/fullness to the sound. I've never owned a vintage Pioneer receiver, so I don't know the sonic characteristics, but it's definitely worth a try.

Try it, and then ask yourself: Do I want more warmth? How would I change the sound if I could?

I actually have the same, or a very similar, Magnavox as you have. It doesn't have enough power for my main speakers, so I only use one channel of it on a mono setup, but that amp is already fairly warm with its 6V6 tubes. It so happens I'm only using a passive pre (the Schiit Sys, really just a volume pot in a two input, one output switch box), and trying something like that would give you insight into a neutral preamp (neither SS nor tube) to also see if you want more of this aspect or that aspect of sound. ThemSys is cheap - just $50 or so to try and I've used them as switchboxes only to compare two different preamps to decide which I like better. My point being that that might not be a bad investment to try not only as a passive pre, but to permanently have on hand as a tool/utility to compare other preamps down the road.

If you stick another warm tube pre in front of it, it may be what you're looking for, or it may be too much of a good thing and make the sound less dynamic and more veiled than you want. You just never know.

You just have to play around with different options. Ideally, you could get in touch with local AK'ers or other audio buffs and have them bring over different preamps (SS and tube), so you could see how it all mates together with your amp and speakers. That's the best way really, and cheaper than buying something, hoping it matches well, and then having to resell and buy another if it doesn't do it for you.
 
captouch said:
You just have to play around with different options. Ideally, you could get in touch with local AK'ers or other audio buffs and have them bring over different preamps (SS and tube), so you could see how it all mates together with your amp and speakers. That's the best way really, and cheaper than buying something, hoping it matches well, and then having to resell and buy another if it doesn't do it for you.
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well, I live in San Antonio, TX and there are not a lot of members here in this area, that I know of. so that can be tough. As for the Schiit Sys, I do already have a volume control hooked up to the 175, but it is more or less a speaker volume control, so I am not sure if that is an Ideal setup. I am considering the Dynaco PAS if I can find it cheap enough. I would like to have something where I can hook up my Turntable and possibly a CD player in the Aux. But any other more budget friendly versions of the Dynaco PAS are greatly appreciated.

James
 
Jbmorrey said:
Ok thanks for the input on the Paint. I guess my question was if I am using a SS preamp for the phono, am I listening to a hybrid? Will a Tube pre for the phono make the system an "All Tube" and make a significant impact?

Thanks,
James
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I think it will make a difference. I have just been going through this dilemma myself. Deciding between a Bench RIAA5 tube preamp and my Kenwood KA5700 phono pre section. What I found is that although the SS preamp allows more 'room' around the instruments, the low end was rather weak. No low extension and sounding overly damped. To me, anything SS that has to have so much feedback to make it sound good, is a detriment to the overall sound. Go with an all tube setup and you probably won't go back.
 
triode17 said:
I think it will make a difference. I have just been going through this dilemma myself. Deciding between a Bench RIAA5 tube preamp and my Kenwood KA5700 phono pre section. What I found is that although the SS preamp allows more 'room' around the instruments, the low end was rather weak. No low extension and sounding overly damped. To me, anything SS that has to have so much feedback to make it sound good, is a detriment to the overall sound. Go with an all tube setup and you probably won't go back.
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I think my main concern is the loss of details. I prefer a warm sound signature, but also like a good crisp treble presence as well. I am enjoying the Magnavox amp with the SS Phono stage, but I am also debating a Dynaco PAS3 as a pre-amplifier, my only concern with the Dynaco is will it warm things up too much, due to as far as I know the model I am considering does not have any modifications to it, and I am not a modding electronics kind of guy!!

Also seems like all of the "Tube phono preamps" I have been looking at are actually not a true tube phono from what I am reading, they are more of a tube buffer.

James
 
I have a local friend that just moved away from a PAS 3 to a vintage SS preamp. His PAS 3 really wasn't redone either - probably original, so it could have had issues that needed addressing, though nothing obvious because he had been using it for some time - just felt something was missing on the low end in particular.

So there's not just one answer.

I can tell you that a very clean, dynamic, dimensional sound can be had from the all tube Aikido design. It's not particularly warm, but sounds very good to me.
 
As a follow up, I figured out what was wrong with the sound of my tube pre, the tube sockets were dirty. This caused a whining noise from the left channel and a thump whenever i tapped the case on the right channel. Just recently, I tested the original 6072's and 6922's and found they had worn out after two years. Without two new pairs, I substituted plain old 12AY7's and 6DJ8's, they work fine. Quiet and musical.
What I didn't do was clean the tube pins/ sockets because it was only supposed to be temporary. Big mistake. Once cleaned, the whining was gone, the thumping was gone and it sounds glorious again. Fully balanced from Bass to Treble. I may change the sockets but need to find good 9 pin with shields. Any suggestions?
 
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