7c vs & 7t Listening testing. Which one Wins...

[Steve Hoffman]

Not that anyone cares but I have both a 7C and a 7T in perfect running condition and there is no contest. The 7C is the clear winner. It has the "sound", it has the glorious midband, it has the 3-D imagery, it has the toobie goodness we love. My 7T was dry sounding, too much top end, no realistic midband to speak of and basically sounded like a generic solid state preamp from the 1960s-70s.

It didn't sound bad, it was OK but it wasn't magic. The 7C has the magic, IMO, of course..

The 7C (mine is from 1961) with Teles in there sound like a real live person is singing. My 7T sounds like a recording of a person.

Sure, the bass is a bit undefined, etc. with the 7C but the good far outweighs the bad.

I took a look on eBay. A clean unmodded 7C is going for 8K now? What kind of croc is this? When did the prices go so high and why? I thought I was getting slagged when I got my dead mint 7C from Kevin Deal at Upscale Audio for 2k in 1998. 8K now? Geez..

 

[jstang]

What does perfect condition mean?


Jk

 

[Steve Hoffman]

Mint, inside and out, everything to spec. The guy kept meticulous records of everything from December, 1961 all the way up to 1995 or so when he sold it to Kevin Deal at Upscale Audio.

 

[mech986]

Not that anyone cares but I have both a 7C and a 7T in perfect running condition and there is no contest. The 7C is the clear winner. It has the "sound", it has the glorious midband, it has the 3-D imagery, it has the toobie goodness we love. My 7T was dry sounding, too much top end, no realistic midband to speak of and basically sounded like a generic solid state preamp from the 1960s-70s.

It didn't sound bad, it was OK but it wasn't magic. The 7C has the magic, IMO, of course..

The 7C (mine is from 1961) with Teles in there sound like a real live person is singing. My 7T sounds like a recording of a person.

Sure, the bass is a bit undefined, etc. with the 7C but the good far outweighs the bad.

I took a look on eBay. A clean unmodded 7C is going for 8K now? What kind of croc is this? When did the prices go so high and why? I thought I was getting slagged when I got my dead mint 7C from Kevin Deal at Upscale Audio for 2k in 1998. 8K now? Geez..

Mint, inside and out, everything to spec. The guy kept meticulous records of everything from December, 1961 all the way up to 1995 or so when he sold it to Kevin Deal at Upscale Audio.

Hi Steve,

Thanks for providing your perspective on this interesting preamp comparison. One wonders whether, aside from the relatively early transistor active components, a recap and other passive upgrades, along with a realignment voicing of the line amp section would give the 7T a better grade? Do both your 7C and 7T test relatively ruler flat, or are there response anomalies evident on scope or trace testing? Do you think the high end on the 7T is so noticeable because the top end is hot, or the mid and bass is reserved?

I would understand that if both are relatively in original condition we have a reasonable comparison, aging wise, but perhaps a "restored" viewpoint would allow the circuitry to show its strong/weak points better?

Just some relative musings on a Saturday night...It seems to always be this question with vintage gear.

 

[Steve Hoffman]

Well, I got the 7T from a guy who had it for years and didn't play it much. It tested fine but the sound was typical dry, uncomplex solid state from the early days. It sounded OK but was a bit bright and slightly harsh in the lower treble, upper mids. A sound I don't much like. I never measured the thing, just played music on it.

The sonic signature was just not one that I would care to hear again on a vintage system. The tubed 7C has such a better sonic signature (and I tried it with Telefunkens, Mullards, Bugle Boys, etc.) and had so much more character that the "deadness" of the 7T was sort of disappointing to me since I got it for so little money and it looked so neat and I expected so much.

Not everyone likes the sound I like though. See, I have modern systems for accurate, clean sound. I endorse a lot of gear and I have two world class systems that I use in my mastering work.

I have the vintage stuff because I like the old sound. The 7T has the sound of the 1970's Japanese receivers. Not a bad sound but nothing I would ever long to hear to relive the past glories of Hi-Fi...

 

[jstang]

Every 7t I have seen or own was in need of new caps and other refurb items.

They benefit greatly from new caps because unlike the 7c, the 7t has electrolytic caps in the signal path. Even has some tantalums that must be upgraded...the tantalums are your typical 70 receiver sound. The 7c has no electrolytic caps in the main signal path which helps with sound and aging issues in general. However, once refurbed fully the 7t sounds much better. And correct modifications brings them to a whole new level.

The 7t simply does not age as well as the 7c. My 7c has new telefunken smoth plates, the caps (ESR tested) and voltages test out fine. So be careful with your baseline of comparison, remember how I started this thread "refurbed modified 7t compared to a clean 7c". Stock un-refurbed 7t is no match for 7c. Recapped & modded is a whole different sound....

Again 6 of one, half dozen of another....

Jk

 

[PB_Audio]

Well, I got the 7T from a guy who had it for years and didn't play it much. It tested fine but the sound was typical dry, uncomplex solid state from the early days. It sounded OK but was a bit bright and slightly harsh in the lower treble, upper mids. A sound I don't much like. I never measured the thing, just played music on it.

The sonic signature was just not one that I would care to hear again on a vintage system. The tubed 7C has such a better sonic signature (and I tried it with Telefunkens, Mullards, Bugle Boys, etc.) and had so much more character that the "deadness" of the 7T was sort of disappointing to me since I got it for so little money and it looked so neat and I expected so much.

Not everyone likes the sound I like though. See, I have modern systems for accurate, clean sound. I endorse a lot of gear and I have two world class systems that I use in my mastering work.

I have the vintage stuff because I like the old sound. The 7T has the sound of the 1970's Japanese receivers. Not a bad sound but nothing I would ever long to hear to relive the past glories of Hi-Fi...

It always amazes me how anyone can assume that 40 year old caps in the signal path could possibly give a fair representation of the sonic character of any audio component...

 

[Steve Hoffman]

It always amazes me how anyone can assume that 40 year old caps in the signal path could possibly give a fair representation of the sonic character of any audio component...

Well, when I did the test it was only 30 years old and everything tested fine. What amazes me is that people switch out caps and do mods to vintage gear in the first place, especially if it doesn't need it. There is no way to sell it for full value when that is done (especially in Asia).

If one wants to do a bunch of mods and changes to 40 year old gear to get a more modern sound, just buy a modern preamp. There are many out there, slightly used, in audiophile land.

 

[Sam Cogley]

Caps age, especially electrolytics. At 30 years old, they were, at best, at the very end of their design lifespan.

Old caps, even ones that test good can cause a circuit to not work properly. Ask anyone who has worked on more than a couple of Technics SP-10s about this.

 

[jstang]

You like disfunction Vintage gear? Why even bother to buy a worn vintage unit and listen to it when it sounds poorly because its worn...I don't have poor sounding hanger queens....

Not to be a total nerd... How did you test it? Seems that you tested with your ears...did not like it....and never refurbed it.

I use an ESR meter and other gear to test before/after I replace caps... also test with a lot of other test equipment.

On the flip side of the coin... A 7t's value is not really going to be adversely affected if it's improved with fresh caps and a few other mods.... Now is it?

Actualliy, a refurbed and upgraded 7t is likely worth far more than a worn stock 7t that sounds worn.

Stock or stock looking 7c is the way to go.... But what value is a 100% stock 7c that sounds degraded because of worn caps or other worn parts? 7c repairs ideally should look 100% stock.


From which ad would you buy a 7t ... A or B?

A. All stock unrestored 7t that sounds crappy because of 36 year old caps. I did not enjoy the sound and neither will you....

B. Refurbed and modified 7t. That sounds great..... You will Love the sound.... I did.

The 7t is not the museum piece that the 7c is....refurb, modify and enjoy the 7t.

Jk

Well, when I did the test it was only 30 years old and everything tested fine. What amazes me is that people switch out caps and do mods to vintage gear in the first place, especially if it doesn't need it. There is no way to sell it for full value when that is done (especially in Asia).

If one wants to do a bunch of mods and changes to 40 year old gear to get a more modern sound, just buy a modern preamp. There are many out there, slightly used, in audiophile land.

 

[Steve Hoffman]

Look, we tested the 7T in the studio. All values were correct. The unit was working properly. Nothing needed upgrading or replacing. It sounded average. Such is life. Nothing to lose sleep over.

Perhaps this is why 7C are going for $8,000.00 now and the 7T is going for $800.00...

Just a guess.

 

[jstang]

Ok... Ok....

As a electrical engineer...I DON'T GUESS. I ask the tough questions. Just would like the specifics of how you tested it....

What kind of test gear is in the studio? What procedures did you use? Was the test equipment calibrated?

Did you do a system level listening test? Or did you look inside the 7t and test voltages and components?

And what values are you talking about when you say all values were correct?

I just would like to know the details.... How do you know nothing needed to be replaced?

Jk

 

[Steve Hoffman]

It was tested by the tech at the best recording studio in LA. He declaired it fit.

Sorry I don't like the sound of the thing (7T). It could be worse: I could rave about how wonderful it is all over the Internet and watch the price double!

 

[jstang]

Oh.. I got it... No first hand details of the testing process used...no idea of the state of components in the unit....no cleaning of the switches...no RCA jack cleaning...no cleaning of the internal connections...no detail testing of the caps....no checking of the power supply...no....

No refurb....and certainly no upgrade...

Just some way out there vague test... You should go back and ask the tech what he did....

Yup I understand fully now.... No wonder you did not like it. Maybe we should start a post "How I hate the sound of old worn audio gear..."

Jk

 

[mech986]

It was tested by the tech at the best recording studio in LA. He declaired it fit.

Sorry I don't like the sound of the thing (7T). It could be worse: I could rave about how wonderful it is all over the Internet and watch the price double!

IMO, that is a valid opinion. It is a real assessment of an unrestored piece of vintage gear.

Oh.. I got it... No first hand details of the testing process used...no idea of the state of components in the unit....no cleaning of the switches...no RCA jack cleaning...no cleaning of the internal connections...no detail testing of the caps....no checking of the power supply...no....

No refurb....and certainly no upgrade...

Just some way out there vague test... You should go back and ask the tech what he did....

Yup I understand fully now.... No wonder you did not like it. Maybe we should start a post "How I hate the sound of old worn audio gear..."

Jk

JK, you obviously also don't like the sound of unrestored gear. You're absolutely right about stuff not aging well. But if you "restored" the 7T with new but exactly the same type of caps, resistors, tantalum caps, etc. as was original, there's a chance the 7T could sound better than stock but still sound poorly against what we have today or know today about components.

Your restoration has come from pretty careful new and different passive component selection and listening tests plus knowledge of later circuit techniques that weren't used or available when the 7T was designed and built. If its a "super 7T", so be it. But not everyone can or wants to modify the 7T for whatever reason they have. That's their prerogative.

From what I know, Steve knows his gear, knows his sound and the sound of live and well recorded music. He does great stuff professionally and has the ability and means to do anything with gear if desired. He didn't pursue modifying the 7T, he moved on. That's ok. Your 7T was never disparaged nor commented on, he just commented on a vintage unrestored stock 7T.

 

[PB_Audio]

Well, when I did the test it was only 30 years old and everything tested fine. What amazes me is that people switch out caps and do mods to vintage gear in the first place, especially if it doesn't need it. There is no way to sell it for full value when that is done (especially in Asia).

If one wants to do a bunch of mods and changes to 40 year old gear to get a more modern sound, just buy a modern preamp. There are many out there, slightly used, in audiophile land.

QUOTE: "What amazes me is that people switch out caps and do mods to vintage gear in the first place, especially if it doesn't need it."
Clearly, from your description, your Model 7T "needed it" badly. Many caps will be beyond their best performance in 20, let alone 30 years.
Is this news to you???

 

[crooner]

I agree with mastering engineer Steve Hoffman here regarding the stock 7T. I also agree with his views on the tubed 7C.

Sid Smith on the interview that appeared on Stereophile back in 2001 had this to say about the 7T:

He also commented the following in regards to tube gear being superior to solid-state:

So no matter how many mods or cap changes or tweaks you do on a 7T, you can never approach a Model 7.

Obviously, Mr. Smith did not want to disparage his own creation (the 7T), but he states the obvious on the sonic shortcomings of the unit.

My experience with both the 7T and 7C mirrors Steve's. There is a reason why the 7C costs ten times as much.

 

[PB_Audio]

I agree with Steve here regarding the stock 7T. I also agree with his views on the tubed 7C.

Sid Smith on the interview that appeared on Stereophile back in 2001 has this to say about the 7T:

He also commented the following in regards to tube gear being superior to solid-state:

So no matter how many mods or cap changes or tweaks you do on a 7T, you can never approach a Model 7. The designer said it!

My experience with both the 7T and 7C mirrors Steve's. There is a reason why the 7C costs ten times as much.

You have never heard my 7T, nor has Sid.
Oh yes, and just to set the record straight, the reason the Model 7/7C costs more than the 7T is purely a question of supply and demand, as with any valuable in limited supply.
...but then, I believe you already knew that.
I seem to recall another quote, which IIRC was also made by Sid Smith in the late 70s, that with a minor mod, which he himself was performing on the Model 7T at that time, that he was very impressed with the Model 7T. I read this here on AK, recently, so it shouldn't be hard to find. I'm sure someone will recall; but I'll look for it when I have time. It's not urgent, as I'm very confident in my 7T and as Sid told us in the late 70s, the 7T is a fine preamp.
With this I certainly agree. My Model 7T compares well in all regards with my Mark Levinson ML-1. I'm not saying exactly equal, but remarkably similar sounding, if not quite as quiet. As far as the tube preamp state of the art, I'll have to point you in the direction of Audio Research Corp (ARC), and even the current top of the line sells for less than a good Marantz Model 7.
Don't get me wrong, the Model 7 is fabulous; but, in proper form, so is the Model 7T. I stand by that.:yes:

 

[crooner]

According to several Boston Audio Society "BAS Speaker" issues (available online for download), the 7T had a reputation for sounding edgy and harsh as early as the mid 1970's. The model was less than ten years old back then.

There are also reports from well reputed sources, that when the 7T came out in December 1965 a lot of trendy folks traded their 7C's for the new model only to come back to the stores several days later wanting to buy their "old" tubed units back!

 

[crooner]

You have never heard my 7T, nor has Sid.

Sid probably would have loved it. As he was proud of his early SS achievements, even if they fell short of his tubed masterpieces.