Princeton Reverb questions

Princeton Reverb questions

What is the difference between the pull-to-boost models and the non
pull-to-boost models? I have passed up a couple of good deals on the
pull-to-boost model recently and decided that unless there is some
great disparity in tone or operation, then I can live with the boost
model. I am planning on using it at home and occasionally will be
jamming in the garage with friends.

The Ampwares site shows a footnote that indicates a pull boost was
added around 1977...other than that, the specs for Princeton Reverb
amps look to be the same for Silverface models '68 to '81.

TIA

Re: Princeton Reverb questions

Based upon the schematic fo a "boost" model on Schematic Heaven, I'd say it
is a totally different amp. The desireable ones are defintely the older
non-boost models, so you will certainly get a better price on the boost
models, but the tone may be disappointing if you aleady know what a good PR
sounds like. There is also a reissue coming out from Fender in July ($799)
which is pretty nice (I saw it at the Amp Show this past weekend).




<blues2use@gmail,com > wrote in message
news:f53702e6-aee9-4ac9-84b6-3743262b21c8@m36g2000hse.googlegroups,com ...
> What is the difference between the pull-to-boost models and the non
> pull-to-boost models? I have passed up a couple of good deals on the
> pull-to-boost model recently and decided that unless there is some
> great disparity in tone or operation, then I can live with the boost
> model. I am planning on using it at home and occasionally will be
> jamming in the garage with friends.
>
> The Ampwares site shows a footnote that indicates a pull boost was
> added around 1977...other than that, the specs for Princeton Reverb
> amps look to be the same for Silverface models '68 to '81.
>
> TIA

Re: Princeton Reverb questions

Steve L wrote:

>
>
>
>
> <blues2use@gmail,com > wrote in message
> news:f53702e6-aee9-4ac9-84b6-3743262b21c8@m36g2000hse.googlegroups,com ...
>> What is the difference between the pull-to-boost models and the non
>> pull-to-boost models? I have passed up a couple of good deals on the
>> pull-to-boost model recently and decided that unless there is some
>> great disparity in tone or operation, then I can live with the boost
>> model. I am planning on using it at home and occasionally will be
>> jamming in the garage with friends.
>>
>> The Ampwares site shows a footnote that indicates a pull boost was
>> added around 1977...other than that, the specs for Princeton Reverb
>> amps look to be the same for Silverface models '68 to '81.
>>
>> TIA
>
> Based upon the schematic fo a "boost" model on Schematic Heaven, I'd say
> it is a totally different amp. The desireable ones are defintely the
> older non-boost models, so you will certainly get a better price on the
> boost models, but the tone may be disappointing if you aleady know what
> a good PR sounds like. There is also a reissue coming out from Fender in
> July ($799) which is pretty nice (I saw it at the Amp Show this past
> weekend).


$64K question. Will it be hard wired?

Re: Princeton Reverb questions

Nope. PCB. But I dare you to hear the difference.



"west" <west@birch,net > wrote in message
news:mZ6dnZTEOfX8LLHVnZ2dnUVZ t3inZ2d@posted.birchtelecom...
> Steve L wrote:
>
>>
>>
>>
>>
>> <blues2use@gmail,com > wrote in message
>> news:f53702e6-aee9-4ac9-84b6-3743262b21c8@m36g2000hse.googlegroups,com ...
>>> What is the difference between the pull-to-boost models and the non
>>> pull-to-boost models? I have passed up a couple of good deals on the
>>> pull-to-boost model recently and decided that unless there is some
>>> great disparity in tone or operation, then I can live with the boost
>>> model. I am planning on using it at home and occasionally will be
>>> jamming in the garage with friends.
>>>
>>> The Ampwares site shows a footnote that indicates a pull boost was
>>> added around 1977...other than that, the specs for Princeton Reverb
>>> amps look to be the same for Silverface models '68 to '81.
>>>
>>> TIA
>> Based upon the schematic fo a "boost" model on Schematic Heaven, I'd say
> > it is a totally different amp. The desireable ones are defintely the
> > older non-boost models, so you will certainly get a better price on the
> > boost models, but the tone may be disappointing if you aleady know what
> > a good PR sounds like. There is also a reissue coming out from Fender in
> > July ($799) which is pretty nice (I saw it at the Amp Show this past
> > weekend).
>
>
> $64K question. Will it be hard wired?

Re: Princeton Reverb questions

On May 15, 6:17 pm, "Steve L" <sur...@sliberty,com > wrote:
> Nope. PCB. But I dare you to hear the difference.
>
> "west" <w...@birch,net > wrote in message
>
> news:mZ6dnZTEOfX8LLHVnZ2dnUVZ t3inZ2d@posted.birchtelecom...
>
>
>
> > Steve L wrote:
>
> >> <blues2...@gmail,com > wrote in message
> >>news:f53702e6-aee9-4ac9-84b6-3743262b21c8@m36g2000hse.googlegroups,com ...
> >>> What is the difference between the pull-to-boost models and the non
> >>> pull-to-boost models? I have passed up a couple of good deals on the
> >>> pull-to-boost model recently and decided that unless there is some
> >>> great disparity in tone or operation, then I can live with the boost
> >>> model. I am planning on using it at home and occasionally will be
> >>> jamming in the garage with friends.
>
> >>> The Ampwares site shows a footnote that indicates a pull boost was
> >>> added around 1977...other than that, the specs for Princeton Reverb
> >>> amps look to be the same for Silverface models '68 to '81.
>
> >>> TIA
> >> Based upon the schematic fo a "boost" model on Schematic Heaven, I'd say
> > > it is a totally different amp. The desireable ones are defintely the
> > > older non-boost models, so you will certainly get a better price on the
> > > boost models, but the tone may be disappointing if you aleady know what
> > > a good PR sounds like. There is also a reissue coming out from Fender in
> > > July ($799) which is pretty nice (I saw it at the Amp Show this past
> > > weekend).
>
> >   $64K question. Will it be hard wired?- Hide quoted text -
>
> - Show quoted text -

Hi Steve,
I am comparing the two schematics AA1164 and the top boost schematics
and I see differences... but nothing that would make me think it is a
totally different amp.
4.7k 1W resistor in the power supply vs 18K 1W.
Different bandpass filter (?) after V1B 1meg-2.2pf vs 3.3meg-10pf.
Different cathode bias for the 12AT7 in the reverb circuit.
220K resistor on the grid of the reverb recovery stage on the
blackface (to bleed off a bit of gain??)
Different load resistor / capacitor value for the bias cuircuit.
Of course the big difference IS the pull boost but for someone who
knows safe hi voltage practices and has the schematic they could
easily defeat this part of the circuit (as well as changing above..
though I can see how some would affect tone more than others)
Not saying that this is "blackfacing" the amp since that would require
changes to lead dress, components, speakers, OT as well as the changes
above (and even then not all BFs sound alike) BUT all of those are
things that are not obvious from just viewing a schematic. What do you
see in the schematic that make a huge difference in tone?
The reason I am curious is that I have a non boost Deluxe reverb that
(.. ok.. maybe I overpayed a bit but still cheaper than earlier SF
Deluxes I have seen). I have never played a BF Deluxe Rv but would
love to understand what the differences are tonaly. (and actually
bought the DR BECAUSE I could not find a reasonably priced Princeton
RV in any model/condition).

I hope I am not talking out of my ass (wouldnt be the first time :D )
but always willing to listen to someone with more experience than me.

Cheers

Drew

Re: Princeton Reverb questions

I am not sure which schematics I looked at last time, but after reading your
post, I went back and looked again, and I have to agree with you - the 1164
and the boost version are quite similar. Sorry for my previous post. The
differences are, as you mentioned, the boost circuit, a few values, and also
some of the reverb circuit is a bit different. Also, the trannies are
different part numbers, but according to what I can find, the available
replacement trannies reference both sets of part numbers, so they mey be
fairly equivalent.


"DH82C" <drew.rsm@gmail,com > wrote in message
news:1b147ff0-98ae-47de-87d2-9b2e4401ce1b@34g2000hsh.googlegroups,com ...
On May 15, 6:17 pm, "Steve L" <sur...@sliberty,com > wrote:
> Nope. PCB. But I dare you to hear the difference.
>
> "west" <w...@birch,net > wrote in message
>
> news:mZ6dnZTEOfX8LLHVnZ2dnUVZ t3inZ2d@posted.birchtelecom...
>
>
>
> > Steve L wrote:
>
> >> <blues2...@gmail,com > wrote in message
> >>news:f53702e6-aee9-4ac9-84b6-3743262b21c8@m36g2000hse.googlegroups,com ...
> >>> What is the difference between the pull-to-boost models and the non
> >>> pull-to-boost models? I have passed up a couple of good deals on the
> >>> pull-to-boost model recently and decided that unless there is some
> >>> great disparity in tone or operation, then I can live with the boost
> >>> model. I am planning on using it at home and occasionally will be
> >>> jamming in the garage with friends.
>
> >>> The Ampwares site shows a footnote that indicates a pull boost was
> >>> added around 1977...other than that, the specs for Princeton Reverb
> >>> amps look to be the same for Silverface models '68 to '81.
>
> >>> TIA
> >> Based upon the schematic fo a "boost" model on Schematic Heaven, I'd
> >> say
> > > it is a totally different amp. The desireable ones are defintely the
> > > older non-boost models, so you will certainly get a better price on
> > > the
> > > boost models, but the tone may be disappointing if you aleady know
> > > what
> > > a good PR sounds like. There is also a reissue coming out from Fender
> > > in
> > > July ($799) which is pretty nice (I saw it at the Amp Show this past
> > > weekend).
>
> > $64K question. Will it be hard wired?- Hide quoted text -
>
> - Show quoted text -

Hi Steve,
I am comparing the two schematics AA1164 and the top boost schematics
and I see differences... but nothing that would make me think it is a
totally different amp.
4.7k 1W resistor in the power supply vs 18K 1W.
Different bandpass filter (?) after V1B 1meg-2.2pf vs 3.3meg-10pf.
Different cathode bias for the 12AT7 in the reverb circuit.
220K resistor on the grid of the reverb recovery stage on the
blackface (to bleed off a bit of gain??)
Different load resistor / capacitor value for the bias cuircuit.
Of course the big difference IS the pull boost but for someone who
knows safe hi voltage practices and has the schematic they could
easily defeat this part of the circuit (as well as changing above..
though I can see how some would affect tone more than others)
Not saying that this is "blackfacing" the amp since that would require
changes to lead dress, components, speakers, OT as well as the changes
above (and even then not all BFs sound alike) BUT all of those are
things that are not obvious from just viewing a schematic. What do you
see in the schematic that make a huge difference in tone?
The reason I am curious is that I have a non boost Deluxe reverb that
(.. ok.. maybe I overpayed a bit but still cheaper than earlier SF
Deluxes I have seen). I have never played a BF Deluxe Rv but would
love to understand what the differences are tonaly. (and actually
bought the DR BECAUSE I could not find a reasonably priced Princeton
RV in any model/condition).

I hope I am not talking out of my ass (wouldnt be the first time :D )
but always willing to listen to someone with more experience than me.

Cheers

Drew

Re: Princeton Reverb questions

So, based on the replies so far, am I correct in assuming that the
differences are nominal and the tonality should be acceptable as compared to
the non-boost model? I really don't want to ante-up the difference in
purchase price although I understand that the non-boost is a more desirable
unit.

I've had almost every (decent) Fender amp made over the years (I'm near 62
and still playing a little). Probably should have kept them all starting
with my Gibson Falcon, a couple of Supros and Ampegs, Princeton Reverb,
Bandmaster Reverb, Dual Showman Reverb, Vibrolux Reverb, Twin Reverb, a
couple of Boogies...you get the picture...back in the old days, amps were
tools and were used and sold as the mood or need struck. Never ever thought
they'd be collector's items...I still don't get the vintage/collector thing
anyway but that's just me. If I own something, I'm going to use it...hence,
the original question about non-boost vs boost...

Thanks for the replies. I appreciate you folks for taking the time to
answer...



<blues2use@gmail,com > wrote in message
news:f53702e6-aee9-4ac9-84b6-3743262b21c8@m36g2000hse.googlegroups,com ...
> What is the difference between the pull-to-boost models and the non
> pull-to-boost models? I have passed up a couple of good deals on the
> pull-to-boost model recently and decided that unless there is some
> great disparity in tone or operation, then I can live with the boost
> model. I am planning on using it at home and occasionally will be
> jamming in the garage with friends.
>
> The Ampwares site shows a footnote that indicates a pull boost was
> added around 1977...other than that, the specs for Princeton Reverb
> amps look to be the same for Silverface models '68 to '81.
>
> TIA

Re: Princeton Reverb questions

In article <dxiXj.1798$bG1.648@trndny04>,
"Bob" <bobstickel@verizon,net > wrote:

> So, based on the replies so far, am I correct in assuming that the
> differences are nominal and the tonality should be acceptable as compared to
> the non-boost model? I really don't want to ante-up the difference in
> purchase price although I understand that the non-boost is a more desirable
> unit.
>
> I've had almost every (decent) Fender amp made over the years (I'm near 62
> and still playing a little). Probably should have kept them all starting
> with my Gibson Falcon, a couple of Supros and Ampegs, Princeton Reverb,
> Bandmaster Reverb, Dual Showman Reverb, Vibrolux Reverb, Twin Reverb, a
> couple of Boogies...you get the picture...back in the old days, amps were
> tools and were used and sold as the mood or need struck. Never ever thought
> they'd be collector's items...I still don't get the vintage/collector thing
> anyway but that's just me. If I own something, I'm going to use it...hence,
> the original question about non-boost vs boost...
>
> Thanks for the replies. I appreciate you folks for taking the time to
> answer...
>
>

There's one thing about the pull-boost circuit which hasn't yet been
mentioned (in this thread, although it's been mentioned a few times over
the year).

The reverb driver tube is working overtime with the pull boost model,
whether or not the boost is active. The cathode resistor is lower in
value than the non-boosted version, increasing the current through the
tube. These amps EAT reverb driver tubes for lunch.

Fortunately, it's fairly straightforward to fix this.

Furthermore, most folks don't care too much about the boosted sound
(it's really grainy). It's not a huge deal to restore this to the
pre-'76 circuit. If you choose to do this, the pull switch can be put
to good use My personal favorite is to use it as a bright switch.

--Mike

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